User:Scellef/Laptop Hardware ID Instructor Guide
This document is intended to serve as a guide for instructors in leading the Laptop Hardware ID course. Each section contains an Abstract, with the core concepts bulleted, and a Lecture, which contains more exposition and detail. Exercises relating to the material presented are included at the end of each section where applicable.
Introduction
Laptop Hardware ID starts with a general overview of notebook computers, their qualities as compared to desktop computers, and a glimpse of how Free Geek handles processing and refurbishment.
Abstract
- Laptops are a complete system (Monitor, Keyboard, "Mouse", Power Supply) in a small package
- Laptops are over-engineered (proprietary pieces, components, etc.)
- Laptops have very few modular components
- Laptop Repair largely consists of cannibalizing one system to make another work
- Different laptop manufacturers do things differently (over-engineered, same problem multiple solutions)
- Common Brands: HP, Dell, IBM/Lenovo, Toshiba, Gateway, Sony
- Our inventory is organized by brand
Re-write:
- Laptops are complete systems (Monitor, Keyboard, "Mouse", Power Supply) in small packages
- Different laptop manufacturers design systems with very different parts
- Laptops have only a few components that are standard across brand and model
- Parts for repair often must come from similar or identical systems
- We organize our build shifts by brand to try and minimize differences
Lynnae 23:35, 28 August 2012 (UTC)
Lecture
Laptops are complete systems. Unlike most desktop and server systems, laptops are designed with displays and input devices (such as keyboards and trackpads) alongside the motherboards and processors that normally constitute a computer system. This may seem like an obvious observation, but it has important implications when considering laptop repair and refurbishment.
One of the key concepts that define desktop computers is modularity. That is to say, almost all of the internal and external components of a desktop system can be swapped out and replaced with entirely different, but compatible, components. This is generally not the case with laptops. If, for instance, you wished to replace the keyboard on a laptop system, you would be relegated to using a keyboard from the exact same model. The replacement would have to have exactly the same shape, with the same mount points and cable, in order to first connect to the laptop, and then fit in such a way that the laptop could properly close its lid. This is true for most pieces of a laptop, and it greatly reduces the potential for repair and refurbishment.
There are some exceptions to this. Very specific components, such as RAM, wireless cards, and hard drives, are generally interoperable between laptops from different manufacturers. These components are the primary things that we recover from the various laptops donated to Free Geek. This is not to say that other items cannot be useful to recover. Instead, we opt to to keep things such as keyboards, hard drive caddies, screens, and so on assembled together in what are referred to as Parts Machines.
If there is one thing to know about laptop computers, it is that they are over-engineered systems. What I mean by this is that the design of laptop computers has presented an interesting and exceptionally difficult engineering problem over the years; specifically, how do you take a fully functional computer system and fit it into something no bigger than a binder? This problem has been met with a myriad of solutions; different companies and different teams of engineers and designers have solved this same problem in a thousand different ways. This has had the unfortunate result of laptops requiring difficult to replace parts, proprietary components and particular pieces of plastic which will fit exactly one model of a laptop and no other. This means repairing and refurbishing laptops is an order of magnitude more difficult and costly than in desktop computer systems.
As you progress through this program, you'll begin by working on laptops which we have designated specifically as Recyclers. In general, these are machines in which we are only interested in recovering a few interoperable components. Later, you'll begin working on As-Is machines; systems that are too old to properly run our operating system, or have some defect which would prevent us from warrantying the system. Finally, you'll be introduced to the Evaluation phase of the program, where you'll help Free Geek sort and classify incoming systems and prepare them for the Laptop Build program.
On the Outside
This section deals with the exteriors of notebook computers.
Abstract
- External anatomy of a laptop (chassis, palm rests, LCD panel assembly, access panels, ports & interfaces)
- Input devices (keyboard, touch pad, pointing stick)
- Access panels and interfaces (USB, PCMCIA, card readers, audio ports)
- Power (battery, power adapters, power supply cables [Figure 8, Mickey Mouse, Dell], power switches)
- Power adapter ratings (wattage = voltage * amperage) and barrels **MOST IMPORTANT**
- Where to find power ratings (underneath the system, underneath the battery, *never* on the battery)
Lecture
Laptops are made up of three primary pieces: the chassis, the screen, and the power supply.
The chassis is the plastic or metal enclosure that constitutes the bottom half of a laptop. It contains the motherboard, hard drive, keyboard, trackpad, and more. Frequently, the bottom of the chassis will have access panels in order to allow easy access to removable and upgradeable components, such as RAM. Along the side of the chassis will be various kinds of ports and interfaces. Some of these, like USB, will allow us to connect external devices like keyboards and hard drives. PCMCIA, or PC Card, slots can fit devices such as external wireless cards. Ethernet ports will allow us to connect to the internet and other networks. Not every laptop will have every kind of interface, with one exception: every laptop will have a jack for connecting its power supply. These jacks can vary greatly between different models and manufacturers, but they'll always be there. Frequently, they'll have a symbol above them that looks something like this:
... ___
Every laptop is going to have at least two user input devices: a keyboard, and a mouse-like device; usually a trackpad. The keyboard is doesn't require much explanation, but you'll sometimes encounter laptops that don't have a trackpad; instead they'll have what is officially referred to as a pointing stick. There are a number of colloquial names for this device that I won't detail here. You will invariably encounter pointing sticks on IBM/Lenovo systems (they call them TrackPoints), and other business-class laptops.
Laptop power supplies can be surprisingly difficult to sort out. In general, most laptops, and in fact most electronics, will have a small message printed somewhere on the chassis that indicates the required rating of its power supply. Usually, this rating can just be found on the underside of the laptop, though occasionally, it will be printed underneath the battery or an access panel. A power supply rating is almost always given in voltage and amperage; for example, something like 19V 3.42A. The rating is important to an extent, but the ultimate deciding factor will always be the barrel, or tip, of the power supply. If a laptop cannot make a reliable connection with its power supply, it won't be able to charge its battery, much less turn on. Unfortunately, some brands have an exceptionally broad range of power adapters, all with different ratings and barrels, for their different models of laptops. HP/Compaq is a prime example of this. In general, you can rely on the following criteria when selecting a power adapter:
- The voltage must match with a margin of error less than one,
- The amperage must be at least as a high as the given rating,
- The barrel must fit securely in the laptop.
An example of the potential confusion that can arise around power supplies: You'll frequently encounter machines that list a rating requiring a power supply with an amperage of 3.42, but won't turn on or charge unless you use a power supply with 4.74 amps. Laptops, despite their designers best intentions, are power-hungry machines and a good, general rule of thumb is: If it doesn't work with what it asks for, give it more! And remember, if the barrel doesn't securely fit, the machine won't power on no matter what kind of rating the power supply has.
Exercises
- Finding Power Adapters (10 - 15 minutes)
- Layout a broad range of laptops with their power supplies in a separate container. Have volunteers read the power ratings and brands and try to find the appropriate adapters.
- Each volunteer should work on at least three different systems
- Make sure the volunteers connect the power adapters to the systems
- Some of the systems won't have amperage printed; advise volunteers to look at brand, voltage, and barrel.
- Some of the systems won't have an exact match for the rating; advise volunteers to look for higher amperage adapters with matching barrels.
- With some laptops, you can use power adapters with voltages different from the ratings on the system (e.g., 18.5V will work on 19V systems)
- "It's the amperage that'll kill you."
Drives and Components
This section introduces various storage devices and components, their interfaces, and their qualities.
Abstract
- Storage Devices (hard drives, optical drives, memory cards)
- Hard drives in detail (SATA vs. IDE, 2.5" vs. 1.8", SSDs, adapters) **MOST IMPORANT**
- Optical drives (CD/DVD-ROM vs. CD/DVD-RW, SATA vs. IDE, proprietary face plates, adapters)
- Memory card (SD, compact flash, Sony memory sticks)
- RAM (types, speeds, sizes)
- Peripheral Cards (Mini PCI, mini PCIe, PCMCIA, Bluetooth and modem cards)
- What distinguishes wireless cards (antennae sockets)
Lecture
Exercises
- RAM Sorting (10 - 15 minutes)
- Hand each volunteer a broad range of different RAM sticks, and a printed RAM chart. Have the volunteers arrange the stacks from left to right by type (SDRAM -> DDR3), and from top to bottom by speed.
- Emphasize the two different ways to refer to RAM (e.g., PC2-3200 vs. DDR2-400)
- Make sure each volunteer has a copy of the RAM Speed & Type Chart
On the Inside
This section deals with the interior makeup of notebook computers. Lectures should be given with systems prepped for hand disassembly.
Abstract
- Motherboards, daughterboards, processors, fan and heatsink asssemblies
- Anatomy of a screen assembly (LCD panel, inverters, bezels, hinges, cables & antennae)
- Splitting the chassis (removing keyboards, how a motherboard fits into a chassis)
- Installing components on motherboards
- Hard drives (SATA, IDE, miscellaneous adapters)
- Wireless cards (MiniPCI, MiniPCIe, PCMCIA, antennae)
- RAM (SDRAM, DDR, DDR2, locations of DIMM sockets)
- Keyboards & trackpads (LIF/ZIF adapters, ribbon cables)