Difference between revisions of "SVANDUSEN Scratch Page"

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|-
 
|-
 
| '''Collect''' ||CPUs will accumulate in two areas:
 
| '''Collect''' ||CPUs will accumulate in two areas:
−
* '''Advanced Testing Incoming Rack''' - there is a covered, foam lined bin on the rack labeled "Incoming CPUs".All CPUs extracted from systems by System Evaluation or other departments and CPUs that have come to the store as customer returns are supposed to be brought and deposited in this container.  CPUs extracted in Advanced Testing during Motherboard triage should be deposited here as well.  
+
* '''Advanced Testing Incoming Rack''' - there is a covered, foam lined bin on the rack labeled "Incoming CPUs".All CPUs extracted from systems by System Evaluation or other departments and CPUs that have come to the store as customer returns are supposed to be brought and deposited in this container.  CPUs extracted in Advanced Testing during Motherboard triage should be deposited here as well.
−
* '''Receiving''' - there is a box on the top shelf of their rack, next to 'Unsorted Memory' labeled 'CPUs'.  In theory, '''all processors with pins are supposed to be brought immediately to us''' by Receiving, however, exceptions do occur.  Other types of CPUs may gather there as well.
+
   
 +
* '''Receiving''' - there is a box on the top shelf of their rack, next to 'Unsorted Memory' labeled 'Processors'.  In theory, '''all processors with pins are supposed to be brought immediately to us''' by Receiving, however, exceptions do occur.  Other types of CPUs may gather there as well.
 +
 
 
* '''At least once a day (preferably twice to three times) the contents of these collection points should be gathered and evaluated.
 
* '''At least once a day (preferably twice to three times) the contents of these collection points should be gathered and evaluated.
 
|-
 
|-
−
| '''Pre-test Evaluation and Storage''' || Evaluate the collected CPUs as follows:
+
| '''Pre-test Evaluation and Storage''' || '''CPUs will not be tested on a daily basis'''.  Some socket types will accumulate more rapidly than others.
−
'''1. Socket Type'''
+
 
−
* Intel 478 and 775 - '''Retain in Pre-test Storage.'''
+
*Intel socket 478 processors will accumulate the fastest and will probably '''need to be tested at least once a week'''.
−
* AMD 754, 939, AM2/AM2+/AM3, Phenom - '''Retain in Pre-test Storage.'''
+
 
−
* Intel other than 478 or 775 (e.g.. 370, slot processors, etc.) - '''Automatic Recycle.'''
+
*Intel socket 775 processors will probably''' need to be tested every two to three weeks'''.
−
* AMD other than 754, 939, AM2/AM2+/AM3 (e.g., 462 [socket A], socket 5, socket 6, etc.) - '''Automatic Recycle.'''
+
 
−
* Non-Intel or AMD (e.g., Cryix, VIA, etc.) - '''Automatic Recycle.'''
+
*AMD socket 754, 939, and AM2 processors will probably '''need to be tested once a month'''.
−
* Non-desktop system processors (e.g., laptops, servers [Intel Xeon, AMD 940, etc.], etc.) - '''Automatic Recycle.'''
+
 
 +
*AMD socket AM2+ and AM3 processors are still extremely rare and '''can be tested whenever it is convenient''' (we currently '''do not''' have an AM3 test board).
 +
 
 +
Pending sufficient accumulation to warrant actual testing, the collected CPUs will be evaluated and stored as described below:
 +
 
 +
Evaluate the collected CPUs as follows:
 +
 
 +
'''1. Socket Type
 +
 
 +
* Intel 478 and 775 - '''Retain in Pre-test Storage'''.
 +
 
 +
* AMD 754, 939, AM2/AM2+/AM3, Phenom - '''Retain in Pre-test Storage'''.
 +
 
 +
* Intel other than 478 or 775 (e.g.. 370, slot processors, etc.) - '''Automatic Recycle'''.
 +
 
 +
* AMD other than 754, 939, AM2/AM2+/AM3 (e.g., 462 [socket A], socket 5, socket 6, etc.) - '''Automatic Recycle'''.
 +
 
 +
* Non-Intel or AMD (e.g., Cryix, VIA, etc.) - '''Automatic Recycle'''.
 +
;
 +
* Non-desktop system processors (e.g., laptops, servers [Intel Xeon, AMD 940, etc.], etc.) - '''Automatic Recycle'''.
 +
 
 +
*'''To differentiate among the AMD socket 754, 939, and AM2 see below:
 +
 
 +
{|fontsize="14" border=".05" fontweight="bold" cellpadding=".5" width="100%" |align="center"|
 +
|-
 +
||[[Image:IMG_5288.JPG |Top of all 3 ]] ||[[Image:754.JPG |Socket 754| ]] ||[[Image:939.JPG |Socket 939]] ||[[Image:AM2.JPG]]
 +
|-
 +
||Top of all 3||754 pins||939 pins||AM2 pins
 +
|}
 +
 
 
'''2. Obvious Physical Damage'''
 
'''2. Obvious Physical Damage'''
−
* Primarily this will be '''bent pins'''.
+
 
−
::This will only occur with PGA (Pin Grid Array) processors; socket 478s, 754s, 939s, AM2s, etc.
+
* Primarily this will be '''bent pins or pins broken off'''.
−
::This is '''not''' necessarily a sign to recycle the processor.  Many can be rescued.  A determination will be made at the actual time of testing.
+
:This will only occur with PGA (Pin Grid Array) processors; socket 478s, 754s, 939s, AM2s, etc.
−
::This step of evaluation is primarily to determine whether there is an inordinate amount of damage occurring prior to their arrival in Advanced Testing so that the sources can be advised and corrective steps taken.
+
 
−
* Very rarely ... there will be signs of scorching; indicating that a major thermal event has taken place sometime during the life of the processor. Again, this is not necessarily a sure indicator that the processor should be recycled unless the damage is obviously severe.  This is a judgment call that experience will teach.
+
:This is '''not''' necessarily a sign to recycle the processor.  Many can be rescued.  A determination will be made at the actual time of testing - '''Retain in Pre-test Storage'''.
 +
 
 +
:If any pins are '''broken off''' - '''Automatic Recycle'''.
 +
 
 +
:This step of evaluation is primarily to determine whether there is an inordinate amount of damage occurring prior to their arrival in Advanced Testing so that the sources can be advised and corrective steps taken.
 +
 
 +
* Very rarely an LGA (Land Grid Array) processor (currently this applies '''only to Intel socket 775''') may have a '''deep scratch''' across one or more of the gold contacts on the face.  This is the equivalent of a '''broken pin''' on a PGA processor and cannot be repaired - '''Automatic Recycle'''.
 +
 
 +
* Very, very rarely ... there will be '''signs of scorching'''; indicating that a major thermal event has taken place sometime during the life of the processor. Again, this is not necessarily a sure indicator that the processor should be recycled unless the damage is obviously severe (melted metal, etc.).  This is a judgment call that experience will teach - '''Retain in Pre-test Storage'''.
 +
 
 +
Put the sorted processors into '''Pre-test Storage''' in TARDIS or into the '''"Bad CPU"''' bin for recycling.
 +
*Those processors going into TARDIS are kept in basically the '''same place as the tested processors'''; on the self, in trays or other containers, in places designated by socket type.  
 
|-
 
|-
−
| Put the sorted processors into Pre-test Storage in TARDIS.
+
| '''Preparation, Evaluation, & Testing''' || When the is accumulation of untested processors in '''Pre-test Storage''' is sufficient to justify testing, bring the trays out of TARDIS for preparation, evaluation, and testing:
−
* This is basically in the same place as the tested processors; on the self, in trays or other containers, in places designated be socket type.
+
 
−
'''3. Sort by Speed'''
+
'''1. Prepare -''' Prepare the CPUs as follows:
−
* SDRAM -
+
 
−
::PC 66  - '''Automatic Recycle.'''
+
:a. Place the Pre-test Storage tray on a work surface.
−
::PC 100 - '''Automatic Recycle.'''
+
 
−
::PC 133 - '''Set aside to sort by capacity.'''
+
:b. Place a drop of solvent on the die (solid, metallic, upper surface) of each processor and smear until coated evenly.
−
*DDR -
+
 
−
::PC 1600 (200 MHz) - '''Automatic Recycle'''.
+
:c. Leave for a minute or so to allow the solvent to work.
−
::PC 2100 (266 MHz) - '''Set aside to sort by capacity.'''
+
 
−
::PC 2700 (333 MHz) - '''Set aside to sort by capacity.'''
+
:d. Use a rag to clean thoroughly clean away '''all''' of the old thermal paste and other material from the die.
−
::PC 3200 (400 MHz) - '''Set aside to sort by capacity.'''
+
 
−
*DDR2 -
+
:e. Replace the processor in the tray and repeat until all of the processors have been cleaned.
−
::PC2 3200 (400 MHz) - '''Set aside to sort by capacity.'''
+
 
−
::PC2 4200 (533 MHz) - '''Set aside to sort by capacity.'''
+
'''2. Evaluate -''' Evaluate the prepared processors as follows:
−
::PC2 5300 (667 MHz) - '''Set aside to sort by capacity.'''
+
 
−
::PC2 6400 (800 MHz) - '''Set aside to sort by capacity.'''
+
:'''a. Processor type'''
−
::PC2 8500 (1066 MHz) - '''Set aside to sort by capacity.'''
+
 
−
::PC2 9600 (1200 MHz) - '''Store in TARDIS until a test board is available.'''
+
:*'''Intel socket 478 -'''
−
'''4. Sort by Capacity'''
+
 
−
*SDRAM -
+
::Pentium 4 with a Frequency (see notes) greater than or equal to 2.4 GHz - '''Retain for Testing'''.
−
::32 thru 128 MB - '''Automatic Recycle'''.
+
 
−
::256, 512 MB, & 1 GB - '''Stack by capacity in designated area on table (orange label) to be loaded into test board.'''
+
::Pentium 4 with a Frequency(see notes) less than 2.4 GHz - '''Automatic Recycle'''.
−
*DDR -
+
 
−
::128, 256, 512 MB, & 1 or 2 GB - '''Stack by capacity in designated area on table (orange label) to be loaded into test board.'''
+
::Celeron or Celeron D - '''Automatic Recycle'''.
−
*DDR2 -
+
 
−
::256 & 512 MB, 1 or 2 GB - '''Stack by capacity in designated area on table (orange label) to be loaded into test board.'''
+
::All 'Confidentials' or blank dies - '''Automatic Recycle'''.
−
'''5. Unspecified speed and/or capacity'''
 
−
:Frequently RAM will not be labeled as to speed or capacity by the manufacturer.  In such cases it is necessary to determine these characteristics by other means.
 
−
*SDRAM -
 
−
:*Insert RAM into the test device in front of monitor (SIMM Check II).
 
−
:*Push red button(On/Off) to power on.
 
−
:*Wait for screen to display "INNOVENTIONS".
 
−
:*Press blue button (F1).
 
−
:*If display ("Basic Test") indicates speed less than 133 MHz - '''Automatic Recycle.'''
 
−
:*If display ("Basic Test") indicates capacity less than 32X64 (256 MB - see chart on test device for other equivalents) - '''Automatic recycle.'''
 
−
:*If display goes past "Basic Test" -  '''press blue F1 button until "Basic Test" is displayed.'''
 
−
:*If display will not hold on "Basic Test" or error message is displayed - '''Automatic recycle.'''
 
−
:*If speed and capacity can be determined, and both meet specification - 
 
−
::'''Press red button (On/Off) to turn off test device.'''
 
−
::'''Remove RAM.'''
 
−
::'''Label with speed and capacity.'''
 
−
::'''Stack in designated area on table (orange label) to be loaded into test board.'''
 
−
*DDR & DDR2 -
 
−
:*Use a test board. Several boards give an accurate reading regarding capacity and speed (see also "Loading & Testing).
 
−
::*Load a single stick.
 
−
::*Power on at the power supply.
 
−
::*Wait until the system enters "MemTest".
 
−
::*Read the capacity and speed from the display.
 
−
::*Power off at the power supply.
 
−
::*Remove the stick.
 
−
::*Label and stack in designated area on table (orange label) to be loaded into test board.
 
−
:*Research online.  Several websites dealing in RAM specifications have been bookmarked and other websites can be accessed by "Googling" using the manufacturer and or model/part number (if available).
 
−
::*Locate a website.
 
−
::*Locate the RAM in question in the website.
 
−
::*Note the capacity and speed in the specifications.
 
−
::*Label and stack in designated area on table (orange label) to be loaded into test board.
 
−
:*Ask an instructor.  Some of them know ways to determine information by examining the imbedded chips.
 
−
'''6. "Kit of 2"'''
 
−
*Some manufacturers, especially '''Kingston''' and '''Super Talent''' have a marketing ploy of packaging RAM in pairs totaling a specific capacity, usually 512 MB and 1 or 2 GB. In these cases, each stick has only '''one half''' of the total capacity; eg. a 1GB "Kit of 2" consists of two 512 MB sticks.
 
−
*This will be indicated somewhere on the label, either as a distinct statement as such or, in the case of '''Kingston''', within the model number; eg. KVR400x64C3A'''K2'''/1G.  In this case the "400" indicates the speed, the "1G" indicates '''the total capacity of the kit''', and the "K2" indicates that the stick is part of the kit.  The actual capacity of the stick in this example is one half of 1 GB or 512 MB.
 
−
*Both halves of such kits are not always present when they come into our possession but they are testable separately.
 
−
*When labeling such sticks after testing, treat each one as a separate stick and label it with its '''actual individual capacity''' (see "Labeling and Routing").
 
−
|-
 
−
| '''Test''' || Test the sorted RAM in the wall-mounted test boards as follows:
 
  
−
'''1. Select -'''Select the RAM to be loaded according to the following criteria:
+
:*'''Intel socket 775 -'''
  
−
*'''Must''' all be of the '''same type'''.
+
::Pentium 4 with a Frequency* greater than or equal to 2.4 GHz - '''Retain for Testing'''.
−
*'''Must''' all be of the '''same speed'''.
 
−
*'''May''' be of '''mixed size'''; ie. 256 and 512, etc.
 
−
*'''Should''' be '''balanced by size''' across channels ('''all''' test boards are "Dual Channel"); ie. 512 MB in channel 1 and 256 MB in channel 2 (see "Load").
 
−
*'''Should''' be all of the '''same brand or paired by brand''', if possible, for compatibility and to resolve "latency" issues (particularly with DDR2).
 
−
:'''Balance and brand''' can be worked around if single sticks are all that are available (see "Boot Up").
 
−
 
 
−
'''2. Load -''' Load the RAM into the test boards as follows:
 
  
−
:'''Be aware ---'''
+
::Pentium 4 with a Frequency* less than 2.4 GHz - '''Automatic Recycle'''.
−
:*Banks (the slots into which the sticks are inserted) are designated 0, 1, 2, & 3 moving from inboard [closest to the CPU] to outboard [farthest from the CPU]).
 
−
:*Channels consist of two banks ('''all''' test boards are dual channel but will operate in single channel mode).
 
  
−
::*Banks may be color coded; ie. two black and two blue.
+
::Celeron and Celeron D - '''Retain for Testing'''.
−
::*Clips on the banks (hinged plastic parts at the ends of the banks that hold the sticks in place) may be color coded; ie. two black and two white.
 
−
::*Some boards may have a separation between pairs of banks, some do not.
 
−
::*Some boards may alternate color coded banks or clips; ie. blue-black-blue-black, or pair them; ie. blue-blue-black-black.
 
−
::*In any case, '''Channels are always composed of pairs of banks.  Either the banks themselves or the clips will be of matching color'''.
 
−
::*Intel cpu boards will nearly always match banks 0 and 2 as channel 1 or A, and banks 1 and 3 as channel 2 or B.
 
−
::*AMD cpu boards will nearly always match banks 0 and 1 as channel 1 or A, and banks 2 and 3 as channel 2 or B.
 
−
:*Load from inboard to outboard.
 
−
:*Load largest capacity inboard to smallest outboard; eg. 1 GB in banks 0 and 2 and 512 MB in banks 1 and 3 or 512 MB in bank 0, 256 MB in bank 1, and 128 MB in bank 2.
 
  
−
:*Insert the stick into the bank.
+
::Pentium D - '''Retain for Testing'''.
  
−
::*Align the notches on the stick with the "key" (the small bar) in the groove of the bank.
+
::Core 2 Duo - '''Retain for Testing'''.
−
::*Make sure that '''both ends''' of the stick are in the groove of the bank.
 
−
::*Press firmly and evenly until the stick moves completely into place along its '''entire length''' and the clips '''click into place in the notches at the end of the stick''' securing it in place.
 
−
::*Manually check all clips to confirm that all are closed properly and the stick is securely in place.  
 
  
−
:*Power on '''using the switch on the power supply''' and, if necessary, the power button switch attached to the test board.
+
:*'''AMD sockets 754, 939, & AM2/AM2+/AM3 -'''
  
−
:*Set the KVM channel to the corresponding number or letter of the test board (orange label w/ arrow on power supply).
+
::Athlon 64 & Athlon 64X2 - '''Retain for Testing'''.
  
−
'''3. Observe boot-up process'''
+
::Opteron - '''Retain for Testing'''.
  
−
*The system should go through a boot up process appropriate to that particular board and its corresponding BIOS version and arrive at the Dynamic Host Configuration Protocol (DHCP followed by a spinning slash mark), indicating that it is booting from the network.
+
::Sempron - '''Automatic Recycle'''.
  
−
:*Changes in total RAM capacity, lack of balance across channels, or issues peculiar to a particular board (eg. "System Fan Not Functioning") may result in the appearance of a prompt message directing you to hit a function key (F1, F2, or F4), ESC, or "any key". in order to continue. '''Do so.''' The system should then continue on to DHCP.
+
:'''b. Pin Damage:'''
  
−
:*Some boards, for whatever reason, may require you to pass through the BIOS.  Simply hit the key indicated by the prompt message, hit ESC, and then hit Enter.  The system should then continue on to DHCP.
+
::There will be a great deal of subjective "judgment call" associated with this step.  The actual process of repairing damage requires a great deal of skill, patience, and delicacy. This is one of those areas wherein you will need to learn by doing.  Don't be afraid to take chances ... "if the patient dies, the patient dies".  Ask instructors or experienced volunteers for help and advice.  The tools you will need are in the box labeled "The Little Things That Count".  Below are guidelines for deciding what to recycle and what may be worth attempting to save. Good Luck!
  
−
*Following the completion of DHCP the system should arrive at a program called MemTest without any additional manipulation.
+
:*'''Intel socket 478 -'''
  
−
'''4. Observe MemTest'''
+
::'''Pentium 4 w/ FSB (Front Side Bus) speed of 400 MHz. -''' More than one or two bent pins or any broken pins - '''Automatic Recycle'''.  Otherwise, attempt to repair.
  
−
*This will be a blue screen with white lettering (occasionally monochrome) that will provide information about the RAM being tested (and the CPU as well).
+
::'''Pentium 4 w/ FSB speed of 533 or 800 Mhz. -''' More than three or four bent pins, any crimped pins, or any broken pins - '''Automatic Recycle'''.  Otherwise, attempt to repair.
  
−
:*A box (outlined in white, dotted lines) in the upper right hand corner will indicate '''"Pass %"''', '''"Test %"''', '''"Test #"''', '''"Testing"''', and '''"Pattern"''' ('''"Testing" and "Pattern" are not relevant for now).  This will indicated what point in the progress of each pass and test has been achieved.
+
:*'''AMD socket 754, 939, & AM2/AM2+/AM3 -'''  
  
−
:*A line labeled "Settings", beginning on the far left of the screen, will provide information about RAM speed and "latency" (latency is not relevant for now).  '''RAM speed is not present in all versions of MemTest.'''
+
::Many of these, particularly the Athlon 64X2s (which are dual core) can be very high end and therefore valuable.  Also, the pins on these processors are somewhat coarser than those on the Intel socket 478s and so are a bit more sturdy and forgiving when it comes to manipulating them.  Unless the damage is really severe; many bent pins, badly crimped pins, or broken pins, go ahead and give it a shot.  Many a seemingly hopeless case has been brought back from the dead.
  
−
:*A row of column headings will appear about halfway down the screen and extend all the way across.  Only '''"WallTime"''', '''"Cached"''', and '''"Pass"''' are relevant.
+
'''3. Test -''' Test the evaluated CPUs as follows:
  
−
::'''WallTime''' indicates how much time has elapsed since MemTest began.
+
:a. Set up the Test Station
−
::'''Cached''' indicates how much total RAM has been loaded onto the board.
+
:*The components for the station are stored in the bottom three drawers of the grey cabinet, next to the HD test racks, and consist of:
−
::'''Pass''' indicates what pass the testing process is on.
 
  
−
'''5. Monitor MemTest'''
+
:::A motherboard platform identical to those located at the Motherboard Testing, Video Card Testing, and Network Device and External HD Testing stations.
  
−
*'''Indications of Failure - '''
+
:::A power supply
  
−
:*'''No video, sometimes accompanied by a series of beeps or video is distorted -'''
+
:::A keyboard
  
−
::*The system will not boot up or show any other video signal '''or'''-
+
:::A small, green, plastic box labeled "The Little Things That Count", containing:
−
::*The video is streaked, broken up into blocks, completely fragmented into dancing pixels, or wildly discolored.
 
−
::*One or more sticks may be bad and/or incompatible; ie. ECC.  '''See "Remedies"'''
 
  
−
:*'''"Red Screen" -''' 
+
::::A power switch
 +
::::A tube of silicon based thermal paste
 +
::::Two small square foam pads
 +
::::A small, flat-head screwdriver (used for straightening pins)
 +
::::A pushpin (used for straightening pins)
 +
::::A plastic card (used for straightening pins)
  
−
::*The most common indicator of failure.
+
:::The motherboards for testing the CPUs labeled with the appropriate socket type.
−
::*The bottom half of the screen turns red, a new set of column headings appears, the section fills with data and '''may''' begin scrolling rapidly.  '''See Remedies.'''
 
−
::*Usually occurs within the first two tests of the first pass but may, occasionally, happen much deeper in the testing process.
 
−
::*One or more sticks have failed.  '''See "Remedies".'''
 
  
−
:*'''"WallTime" is frozen -'''
+
::*The sorting table for RAM Testing is ideal for setting up the CPU Test Station.  It has an LCD monitor and power cord available for the purpose.
  
−
::*The clock stops ticking ... period.
+
::*Assemble the platform with the appropriate motherboard and connect the components '''(be sure to plug in the power supply)'''.
−
::*This may happen very early in the testing process or may occur much deeper.
 
−
::*One or more sticks have failed.  '''See "Remedies".'''
 
  
−
:*'''"Cached" column indicates a different total capacity than the known amount physically loaded -'''  
+
:b. Unlatch or otherwise remove the Heat sink/fan assembly from the socket and apply a '''very small''' amount of thermal paste to the area that will cover the die on the processor.  Smear the paste around to create a thin film.  You will need to repeat this from time to time during the testing process.
  
−
::*The total capacity of RAM indicated by this column '''must equal''' the known total capacity of the RAM physically loaded onto the board.
+
:c. On the socket 775 board, it will be necessary to remove the '''Socket Protector'''.
−
::*If not ... this indicates that '''the system is not reading all of the RAM that has been loaded.'''
 
−
::*It is '''permissible for the speed indicated by MemTest to differ''' from the speed indicated on the stick (it will simply run at a slower speed ... this is not optimal but acceptable).
 
−
::*'''This may NOT be a problem with the RAM.'''  This may be a '''problem with one or more of the banks on the test board.'''  
 
−
::*One or more sticks and/or banks have failed.  '''See "Remedies."'''
 
  
−
*'''Remedies - '''
+
:d. Select a processor from the Pre-test Storage tray and insert it into the socket. 
  
−
:This can be tedious, time consuming, and tricky, but with the technology available it is the only way.
+
::There will be various visual cues to enable proper alignment that are specific to each manufacturer and socket type.
 +
:'''
 +
::*Intel socket 775s (a LGA socket) will have two notches on the processor platform that will align with two tabs on the socket frame.
  
−
*'''Red Screen - ''' here there is an important clue.
+
::*Intel socket 478s and all of the AMDs (PGA sockets) will have small gold triangles on the processor platforms that will align with similar triangle markings on the socket frame.
  
−
:*A new row of column headings will appear above the red area (the bottom half of the MemTest screen).  Only '''Test, Pass, and Failing Address''' are relevant here.
+
::*The Intel socket 478s and the AMDs are ZIF (Zero Insertion Force) sockets which means that it should take little or no pressure to get the processor to drop completely into place.
  
−
::*'''Test and Pass''' will indicate at what point in the testing process the failure occurred.  If it occurs early (eg. pass 0, test 1), all well and good.  If it occurs deeper in the testing process, it may be that a failing stick will begin testing well and then fail, making it more difficult to identify.
+
::*'''If any resistance is encountered''', a further inspection of the processor should be made to determine whether or not there are any bent pins. Correct as necessary (or possible).
−
::*'''Failing Address''' is in two parts which indicate the '''pattern''' (not relevant here) and the point in the '''total capacity''' at which the failure occurred.
 
  
−
:*Moving from '''outboard to inboard''', subtract the capacity of each stick from the total until you are in the range at which the failure occurred, eg. four sticks of 256 MB RAM for a total of 1 GB have been loaded.  A failure occurs at 368.2 MB on pass 0, test 1.  The failure has occurred between 512 MB, and 256 MB.  Subtracting 256 MB for each of the two outboard sticks (banks 3 & 2) leaves 512 MB. The failure occurred at a point below this capacity. The failure occurred at a point greater than 256 MB, the capacity of the first inboard stick (bank 0).  Therefore, it is most likely that the stick in bank 1 is the stick that failed.
+
:e. With your left hand, place the Heat sink/fan assembly onto the processor and align it so that it sits evenly.  Apply gentle but firm pressure and maintain until the test is complete.  
−
:*Power off at the switch on the power supply
+
:'''
−
:*Remove the suspected stick.
+
:f. With your right hand, turn on the power switch (make sure the power switch on the power supply is turned on as well).
−
:*Restart the testing process and monitor MemTest again for failures.
 
  
−
*'''No Video or Cached column indicates lower total capacity than physically loaded.'''
+
:g. Observe the LCD monitor.  
  
−
:*This may simply be a matter of the sticks not being seated properly, '''or''' the system does not recognize the RAM '''in the order''' in which it was loaded, '''or''' it has compatibility issues with brands, latency, etc., '''OR''' it has some other problem all its own and refuses to give you any indication as to what it might be.
+
::'''If the small green LED stops blinking and remains steady''', this is a good sign.  The monitor should soon display a logo screen or a POST screen (if necessary take the necessary steps to get to the POST screen). These screens will vary from manufacturer to manufacturer. This is what you are looking for. This is the indication that the CPU is receiving, processing, and retransmitting data to and from the system.  '''The CPU has passed'''.
−
:*Power off at the switch on the power supply.
 
−
:*Remove and re-seat '''all of the sticks.'''
 
−
:*Change the order, re-balance the load across the channels, reverse the channel position by pairs, etc.
 
−
:*Restart the test process and monitor MemTest again for failures.
 
−
   
 
−
*'''WallTime freezes or the location steps for Red Screen, No Video, or Cached column differential don't resolve the issue.'''
 
  
−
:*Unfortunately ... it's strictly trial and error from here on.
+
::'''If the LED continues to blink''', the LCD monitor remains blank, and it is difficult or impossible to shut off the system with the onboard power switch, '''the CPU has almost certainly failed'''.  Be cautious, however, particularly at the beginning of a test run. If you are getting an unusual number of apparent failures (even in the middle of a test run):
−
:*Power off at the switch on the power supply.
+
:'''
−
:*Remove the suspected stick or sticks, singly or in pairs.
+
:::Check all of your connections, particularly the 'plus four' from the power supply, and the VGA cable.
−
:*Restart the testing process and monitor MemTest again for failures.
 
  
−
:*Repeat as necessary until issues are resolved.
+
:::Check the RAM.  Try a different stick of known good RAM.
  
−
*'''If a bad bank or other system failure is suspected for any reason - '''
+
:::Retest a known good processor.
  
−
:*Power off at the switch on the power supply.
+
:::Retest the suspect processor.  If the result is still negative, you can have confidence in the result and '''the CPU has failed'''.  
−
:*Remove '''all RAM sticks.'''
 
−
:*Test '''each bank''' with a '''known good''' RAM stick.
 
  
−
::*If all banks pass, all well and good.  If '''not''', power down, remove, stick or sticks, mark the suspected bank or banks with a label, and notify an instructor.
+
:::Once you have established confidence in your results, you may proceed without repeating the above steps until another suspected anomaly occurs.
−
::*If something other than a bad bank or banks is suspected, ie. video or network issues, ask an instructor.
 
  
−
'''6. For the duration of the testing process - '''
+
:h. When success or failure have been determined, turn off the power to the motherboard, either at the onboard switch or the power supply, and remove the CPU from the socket.
  
−
*'''Check on the progress of the testing process.'''
+
:i. If the test was successful, label, as shown below, and place in tray to be sorted and either stored or passed along to Online Sales.
  
−
*The time necessary to complete the testing process can vary greatly, depending on the capacity and speed of the RAM that has been loaded, the FSB (Front Side Bus) speed of the CPU or other factors specific to the test board.  The time can be less than one hour, with low capacity and/or high speed, or can take an incredibly long time with high capacity and/or low speed (eg. 2 GB of SDRAM at 133 MHz can take nearly 24 hours).  Generally an average load of around 1 GB  of DDR or DDR2 will take between 2.5 and 3.5 hours.
+
Insert images of labeled processors
−
*A complete testing process consists of '''three passes, labeled 0-2.''' 
 
−
*Each pass consists of ''''eight tests, labeled 1-8.'''
 
−
*MemTest will continue to run indefinitely until is manually discontinued.
 
−
*If the pass number is '''3 or greater''', the testing process is complete.
 
  
−
*'''Watch for indications of failure, as indicated above, and correct as necessary.'''
+
:j. If the test was a failure, place the CPU in the "Bad CPUs" bin for recycling.
  
−
'''7. Repeat these steps for each test board as long as there is RAM to be tested.
+
:k. Repeat these steps until the test run is complete.
  
−
'''8. Do NOT load any boards after 5:00P.'''
+
:l. Dismantle the test station and return the components to the storage cabinet.
 
|-
 
|-
−
| '''Label & Route''' ||After the testing process has been completed, label and route the tested RAM as follows:  
+
| '''Sorting & Routing''' ||After the testing process has been completed, sort and route the tested CPUs as follows:  
 +
:'''
 +
'''1. Sort the CPUs by Frequency/L2 Cache/FSB -'''.
  
−
'''1. Unload the test boards -''' .
+
*During the testing and labeling process you should have established the above statistics for each processor and marked them accordingly.
  
−
*Power off at the switch on the power supply.
+
*Sort first by processor type (e.g., P4, Pentium D, Athlon 64, Opteron, etc.).
  
−
*Remove '''all''' RAM sticks and take them to the table to be labeled.
+
*Sort next by FSB.
  
−
*'''If possible''', remove any old, handwritten labeling to avoid confusion.
+
*Sort next by L2 Cache.
  
−
'''2. Label as follows:'''
+
*Sort last by Frequency.
  
−
*'''SDRAM -''' capacity and speed only. Eg. 256/133.
+
'''2. Route the sorted CPUs as follows -'''
  
−
*'''DDR & DDR2 -''' type '''and''' capacity and speed.  Eg. DDR2 512/667.   
+
*Check the supply in the Motherboard Testing kit.  Fill in any obvious gaps.  Consult with the Motherboard Testing volunteers or instructor regarding this.
−
:DDR and DDR2 have more subtle visual cues (other than the label) and can be easily confused by after-testing users such as build.  Therefore, it is '''highly advisable''' to make them as distinguishable as possible.
 
  
−
*'''Kit of 2 -'''  
+
*Co-mingle the tested CPUs with the processors already in storage -'''
  
−
:*Label each stick with its '''true capacity''' and speed.  Eg. a 1GB kit of 2 - each stick would be labeled as 512 MB with the speed.
+
:Follow the established pattern as closely as possible.
−
:*If you have '''both halves''' of such a kit, make a small '''nonstick''' paper strip label, write "Kit of 2" and "xxx MB (or GB) each" on it, wrap it around the kit, and rubber band it together.
+
   
 +
:Shift processors around as needed.
  
−
'''3. Route as follows -'''
+
:Space is '''definitely at a premium''' with some processor and socket types, so use your judgment and imagination.
  
−
*'''The two boxes on the table labeled, "Tested RAM SDRAM & DDR" and "Tested RAM DDR2" -'''
+
*Pass as many tested CPUs on to Online Sales as possible -'''
  
−
:*Place the vast majority of the labeled RAM in the appropriate slots in these two boxes (see '''Store''' for exceptions).
+
:Intel socket 478 - P4s - any Frequency/L2 Cache/FSB - '''pass on in lots of 10'''.  
−
:*This will be harvested regularly by build and occasionally by the store to fill their needs.
 
  
−
*'''TARDIS -'''
+
:Intel Socket 775 - P4s, Celeron, or Celeron D - any Frequency/L2 Cache/FSB - '''pass on in lots of 10'''.
  
−
:*The boxes on the table will populate quite rapidly.
+
:Intel socket 775 - Pentium D, or Core 2 Duo - '''pass on all'''.  
−
:*As they fill (usually once a week or more), empty the slots into the '''appropriate''' static free bags in the '''blue bins''' on the shelf in TARDIS.
 
−
:*As the bags fill, tape them shut and place them in the '''RAM Overstock''' bin on the top shelf.
 
−
:*Replace the bag with an empty one labeled with type, capacity, speed (in MHz) and PC or PC2 code (PC 2100, PC 2700 ... PC2 4200, PC2 5300 ... etc.)
 
−
:*These will be harvested by build and the store to meet their needs.
 
  
−
*'''Store -'''
+
:AMD socket 939 and AM2 - Athlon 64X2 - '''pass on all'''.
  
−
:*Some tested RAM should be '''taken directly to the store''' (do not put in the outgoing "Store" box on the rack shelf next to the TARDIS door).
+
:AMD any socket - Sempron or Opteron - '''pass on all'''.
  
−
::'''SDRAM -'''
+
*Retain the remainder in TARDIS for use by Build, sales in the Thrift Store, and accumulation toward Online Sales.
−
::*1GB/133
 
  
−
::'''DDR -'''
+
'''CONGRATULATIONS ... YOU'RE DONE!!! ... NOW GO WASH YOUR HANDS!!!
 +
[[Image:Example.jpg]]
 +
|-
 +
|}
 +
Notes:
  
−
::*1GB/any speed.
+
'''Frequency, L2 Cache, and FSB''' are categories used to determine the capabilities of a processor.
−
::*512/400 - pairs (or more ) of quality brands (Hynix, Nanya, Samsung, etc.).  '''Leave singles in the box for build.'''
 
  
−
::'''DDR2 -'''
+
:*Frequency refers to the rate at which the CPU processes data e.g., 3.0 GHz. (Gigahertz).
  
−
::*1 or 2 GB/any speed.
+
:*L2 Cache refers to the capacity of a designated portion of the CPU architecture to store short term instructions.
−
::*256 or 512/667 or higher.
 
  
−
::'''All PAIRED & BUNDLED Kit of 2 sets.'''
+
:*FSB (Front Side Bus) refers to the rate at which the CPU transfers data between itself and the 'North bridge'.
  
−
::'''Any sticks, paired or not, any capacity and speed, with "heat spreader" technology''' ... metal plates over the embedded chips that run the length of the stick on one or both sides.
+
*These terms are relevant here '''only for evaluation, labeling, sorting, and routing purposes'''. They each have very involved technical definitions and meanings that are far too involved to go into here. For more information, please ask and instructor, an experienced volunteer, or consult online sources such as Wikipedia.
−
|-
+
−
| '''End of DAY''' ||
+
*The specific information in these categories pertaining to an individual CPU can be obtained as follows:
−
'''POWER OFF ALL TEST BOARDS AT THE SWITCH ON THE POWER SUPPLY WHETHER THE TESTING PROCESS IS COMPLETE OR NOT!'''
+
 
 +
:'''Intel socket 478s and 775s -''' The information is engraved on the die of the processor directly below the processor type.  It will be listed in the form Frequency/L2 Cache/FSB.
 +
 
 +
:'''AMD socket 754s, 939s, AM2s, etc. -''' The information will be located in "The Book of CPUs", and found by referencing model number '''and''' part number.  Ask an instructor or experienced volunteer to assist you.

Latest revision as of 14:45, 12 January 2011

CPU (Processor) Testing

SVANDUSEN 19:13, 26 May 2010 (UTC)

CPUs are the "brains of the computer system. This is where all of the information and instructions are gathered from, processed, and redistributed to the other components of the system. The following will be a description of a VERY RUDIMENTARY TEST to determine the viability of a CPU to function in a system. In actuality, there are a multitude of details and issues involved that would take far more space to cover and time to perform than is practical in these circumstances. This is a very basic overview of the essentials that are necessary to get through the process. For more information please consult other experienced volunteers, instructors, or research such sources as Wikipedia or forums on Google.
STEPS NOTES AND DETAILED INSTRUCTIONS
Collect CPUs will accumulate in two areas:
  • Advanced Testing Incoming Rack - there is a covered, foam lined bin on the rack labeled "Incoming CPUs".All CPUs extracted from systems by System Evaluation or other departments and CPUs that have come to the store as customer returns are supposed to be brought and deposited in this container. CPUs extracted in Advanced Testing during Motherboard triage should be deposited here as well.
  • Receiving - there is a box on the top shelf of their rack, next to 'Unsorted Memory' labeled 'Processors'. In theory, all processors with pins are supposed to be brought immediately to us by Receiving, however, exceptions do occur. Other types of CPUs may gather there as well.
  • At least once a day (preferably twice to three times) the contents of these collection points should be gathered and evaluated.
Pre-test Evaluation and Storage CPUs will not be tested on a daily basis. Some socket types will accumulate more rapidly than others.
  • Intel socket 478 processors will accumulate the fastest and will probably need to be tested at least once a week.
  • Intel socket 775 processors will probably need to be tested every two to three weeks.
  • AMD socket 754, 939, and AM2 processors will probably need to be tested once a month.
  • AMD socket AM2+ and AM3 processors are still extremely rare and can be tested whenever it is convenient (we currently do not have an AM3 test board).

Pending sufficient accumulation to warrant actual testing, the collected CPUs will be evaluated and stored as described below:

Evaluate the collected CPUs as follows:

1. Socket Type

  • Intel 478 and 775 - Retain in Pre-test Storage.
  • AMD 754, 939, AM2/AM2+/AM3, Phenom - Retain in Pre-test Storage.
  • Intel other than 478 or 775 (e.g.. 370, slot processors, etc.) - Automatic Recycle.
  • AMD other than 754, 939, AM2/AM2+/AM3 (e.g., 462 [socket A], socket 5, socket 6, etc.) - Automatic Recycle.
  • Non-Intel or AMD (e.g., Cryix, VIA, etc.) - Automatic Recycle.
  • Non-desktop system processors (e.g., laptops, servers [Intel Xeon, AMD 940, etc.], etc.) - Automatic Recycle.
  • To differentiate among the AMD socket 754, 939, and AM2 see below:
Top of all 3 754.JPG Socket 939 AM2.JPG
Top of all 3 754 pins 939 pins AM2 pins

2. Obvious Physical Damage

  • Primarily this will be bent pins or pins broken off.
This will only occur with PGA (Pin Grid Array) processors; socket 478s, 754s, 939s, AM2s, etc.
This is not necessarily a sign to recycle the processor. Many can be rescued. A determination will be made at the actual time of testing - Retain in Pre-test Storage.
If any pins are broken off - Automatic Recycle.
This step of evaluation is primarily to determine whether there is an inordinate amount of damage occurring prior to their arrival in Advanced Testing so that the sources can be advised and corrective steps taken.
  • Very rarely an LGA (Land Grid Array) processor (currently this applies only to Intel socket 775) may have a deep scratch across one or more of the gold contacts on the face. This is the equivalent of a broken pin on a PGA processor and cannot be repaired - Automatic Recycle.
  • Very, very rarely ... there will be signs of scorching; indicating that a major thermal event has taken place sometime during the life of the processor. Again, this is not necessarily a sure indicator that the processor should be recycled unless the damage is obviously severe (melted metal, etc.). This is a judgment call that experience will teach - Retain in Pre-test Storage.

Put the sorted processors into Pre-test Storage in TARDIS or into the "Bad CPU" bin for recycling.

  • Those processors going into TARDIS are kept in basically the same place as the tested processors; on the self, in trays or other containers, in places designated by socket type.
Preparation, Evaluation, & Testing When the is accumulation of untested processors in Pre-test Storage is sufficient to justify testing, bring the trays out of TARDIS for preparation, evaluation, and testing:

1. Prepare - Prepare the CPUs as follows:

a. Place the Pre-test Storage tray on a work surface.
b. Place a drop of solvent on the die (solid, metallic, upper surface) of each processor and smear until coated evenly.
c. Leave for a minute or so to allow the solvent to work.
d. Use a rag to clean thoroughly clean away all of the old thermal paste and other material from the die.
e. Replace the processor in the tray and repeat until all of the processors have been cleaned.

2. Evaluate - Evaluate the prepared processors as follows:

a. Processor type
  • Intel socket 478 -
Pentium 4 with a Frequency (see notes) greater than or equal to 2.4 GHz - Retain for Testing.
Pentium 4 with a Frequency(see notes) less than 2.4 GHz - Automatic Recycle.
Celeron or Celeron D - Automatic Recycle.
All 'Confidentials' or blank dies - Automatic Recycle.
  • Intel socket 775 -
Pentium 4 with a Frequency* greater than or equal to 2.4 GHz - Retain for Testing.
Pentium 4 with a Frequency* less than 2.4 GHz - Automatic Recycle.
Celeron and Celeron D - Retain for Testing.
Pentium D - Retain for Testing.
Core 2 Duo - Retain for Testing.
  • AMD sockets 754, 939, & AM2/AM2+/AM3 -
Athlon 64 & Athlon 64X2 - Retain for Testing.
Opteron - Retain for Testing.
Sempron - Automatic Recycle.
b. Pin Damage:
There will be a great deal of subjective "judgment call" associated with this step. The actual process of repairing damage requires a great deal of skill, patience, and delicacy. This is one of those areas wherein you will need to learn by doing. Don't be afraid to take chances ... "if the patient dies, the patient dies". Ask instructors or experienced volunteers for help and advice. The tools you will need are in the box labeled "The Little Things That Count". Below are guidelines for deciding what to recycle and what may be worth attempting to save. Good Luck!
  • Intel socket 478 -
Pentium 4 w/ FSB (Front Side Bus) speed of 400 MHz. - More than one or two bent pins or any broken pins - Automatic Recycle. Otherwise, attempt to repair.
Pentium 4 w/ FSB speed of 533 or 800 Mhz. - More than three or four bent pins, any crimped pins, or any broken pins - Automatic Recycle. Otherwise, attempt to repair.
  • AMD socket 754, 939, & AM2/AM2+/AM3 -
Many of these, particularly the Athlon 64X2s (which are dual core) can be very high end and therefore valuable. Also, the pins on these processors are somewhat coarser than those on the Intel socket 478s and so are a bit more sturdy and forgiving when it comes to manipulating them. Unless the damage is really severe; many bent pins, badly crimped pins, or broken pins, go ahead and give it a shot. Many a seemingly hopeless case has been brought back from the dead.

3. Test - Test the evaluated CPUs as follows:

a. Set up the Test Station
  • The components for the station are stored in the bottom three drawers of the grey cabinet, next to the HD test racks, and consist of:
A motherboard platform identical to those located at the Motherboard Testing, Video Card Testing, and Network Device and External HD Testing stations.
A power supply
A keyboard
A small, green, plastic box labeled "The Little Things That Count", containing:
A power switch
A tube of silicon based thermal paste
Two small square foam pads
A small, flat-head screwdriver (used for straightening pins)
A pushpin (used for straightening pins)
A plastic card (used for straightening pins)
The motherboards for testing the CPUs labeled with the appropriate socket type.
  • The sorting table for RAM Testing is ideal for setting up the CPU Test Station. It has an LCD monitor and power cord available for the purpose.
  • Assemble the platform with the appropriate motherboard and connect the components (be sure to plug in the power supply).
b. Unlatch or otherwise remove the Heat sink/fan assembly from the socket and apply a very small amount of thermal paste to the area that will cover the die on the processor. Smear the paste around to create a thin film. You will need to repeat this from time to time during the testing process.
c. On the socket 775 board, it will be necessary to remove the Socket Protector.
d. Select a processor from the Pre-test Storage tray and insert it into the socket.
There will be various visual cues to enable proper alignment that are specific to each manufacturer and socket type.
  • Intel socket 775s (a LGA socket) will have two notches on the processor platform that will align with two tabs on the socket frame.
  • Intel socket 478s and all of the AMDs (PGA sockets) will have small gold triangles on the processor platforms that will align with similar triangle markings on the socket frame.
  • The Intel socket 478s and the AMDs are ZIF (Zero Insertion Force) sockets which means that it should take little or no pressure to get the processor to drop completely into place.
  • If any resistance is encountered, a further inspection of the processor should be made to determine whether or not there are any bent pins. Correct as necessary (or possible).
e. With your left hand, place the Heat sink/fan assembly onto the processor and align it so that it sits evenly. Apply gentle but firm pressure and maintain until the test is complete.
f. With your right hand, turn on the power switch (make sure the power switch on the power supply is turned on as well).
g. Observe the LCD monitor.
If the small green LED stops blinking and remains steady, this is a good sign. The monitor should soon display a logo screen or a POST screen (if necessary take the necessary steps to get to the POST screen). These screens will vary from manufacturer to manufacturer. This is what you are looking for. This is the indication that the CPU is receiving, processing, and retransmitting data to and from the system. The CPU has passed.
If the LED continues to blink, the LCD monitor remains blank, and it is difficult or impossible to shut off the system with the onboard power switch, the CPU has almost certainly failed. Be cautious, however, particularly at the beginning of a test run. If you are getting an unusual number of apparent failures (even in the middle of a test run):
Check all of your connections, particularly the 'plus four' from the power supply, and the VGA cable.
Check the RAM. Try a different stick of known good RAM.
Retest a known good processor.
Retest the suspect processor. If the result is still negative, you can have confidence in the result and the CPU has failed.
Once you have established confidence in your results, you may proceed without repeating the above steps until another suspected anomaly occurs.
h. When success or failure have been determined, turn off the power to the motherboard, either at the onboard switch or the power supply, and remove the CPU from the socket.
i. If the test was successful, label, as shown below, and place in tray to be sorted and either stored or passed along to Online Sales.

Insert images of labeled processors

j. If the test was a failure, place the CPU in the "Bad CPUs" bin for recycling.
k. Repeat these steps until the test run is complete.
l. Dismantle the test station and return the components to the storage cabinet.
Sorting & Routing After the testing process has been completed, sort and route the tested CPUs as follows:

1. Sort the CPUs by Frequency/L2 Cache/FSB -.

  • During the testing and labeling process you should have established the above statistics for each processor and marked them accordingly.
  • Sort first by processor type (e.g., P4, Pentium D, Athlon 64, Opteron, etc.).
  • Sort next by FSB.
  • Sort next by L2 Cache.
  • Sort last by Frequency.

2. Route the sorted CPUs as follows -

  • Check the supply in the Motherboard Testing kit. Fill in any obvious gaps. Consult with the Motherboard Testing volunteers or instructor regarding this.
  • Co-mingle the tested CPUs with the processors already in storage -
Follow the established pattern as closely as possible.
Shift processors around as needed.
Space is definitely at a premium with some processor and socket types, so use your judgment and imagination.
  • Pass as many tested CPUs on to Online Sales as possible -
Intel socket 478 - P4s - any Frequency/L2 Cache/FSB - pass on in lots of 10.
Intel Socket 775 - P4s, Celeron, or Celeron D - any Frequency/L2 Cache/FSB - pass on in lots of 10.
Intel socket 775 - Pentium D, or Core 2 Duo - pass on all.
AMD socket 939 and AM2 - Athlon 64X2 - pass on all.
AMD any socket - Sempron or Opteron - pass on all.
  • Retain the remainder in TARDIS for use by Build, sales in the Thrift Store, and accumulation toward Online Sales.

CONGRATULATIONS ... YOU'RE DONE!!! ... NOW GO WASH YOUR HANDS!!! File:Example.jpg

Notes:

Frequency, L2 Cache, and FSB are categories used to determine the capabilities of a processor.

  • Frequency refers to the rate at which the CPU processes data e.g., 3.0 GHz. (Gigahertz).
  • L2 Cache refers to the capacity of a designated portion of the CPU architecture to store short term instructions.
  • FSB (Front Side Bus) refers to the rate at which the CPU transfers data between itself and the 'North bridge'.
  • These terms are relevant here only for evaluation, labeling, sorting, and routing purposes. They each have very involved technical definitions and meanings that are far too involved to go into here. For more information, please ask and instructor, an experienced volunteer, or consult online sources such as Wikipedia.
  • The specific information in these categories pertaining to an individual CPU can be obtained as follows:
Intel socket 478s and 775s - The information is engraved on the die of the processor directly below the processor type. It will be listed in the form Frequency/L2 Cache/FSB.
AMD socket 754s, 939s, AM2s, etc. - The information will be located in "The Book of CPUs", and found by referencing model number and part number. Ask an instructor or experienced volunteer to assist you.
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