After my post about the perils of used laptops, I received a number of letters from people asking about a point I made regarding the replacement of LCD screens, a typical early casualty on laptops.

Well, detectivekit.com has an excellent tutorial on how to replace a broken LCD, with some helpful photos and important caveats if you decide to give it a go. You don't even need much in the way of tools, just a small phillips screwdriver, some common sense, and a good amount of patience.

The site does a good job of walking you through the steps, but I wanted to offer a few additional points of advice that aren't covered in the tutorial. Namely:

• Before you get started, do a thorough web search on the laptop vendor's website (or the net in general) for the specific model computer you're working on and its "service manual." This is a key phrase used by all vendors that detail exactly how to disassemble and reassemble a notebook. If you can't find a service manual for your PC, many can be disassembled with generic instructions, but many have tricks that you won't find in a million years without documentation. (Old HP notebooks had hidden switches for removing the keyboard placed between the function keys, for example.)
• You may not need a full LCD screen at all. If your screen is blank, try replacing the LCD inverter before you go whole hog and replace the entire display. The inverter is a small component that fits in the base of the laptop and connects the screen to the motherboard. It gets quite hot and thus it tends to burn out quickly... but it's only a $20 or $30 part, vs. up to $300 for a full LCD. It's also easier to replace since you need not disassemble the screen to swap it in. Your service manual will show you how to do this, but the procedure is different than replacing an LCD.
• Label your screws very carefully. Laptops come chuck full of screws of a wide variety of shapes and sizes. When you reassemble your machine, you'll need to get all the screws back in all the right holes. I usually use Dixie cups to organize what goes where.
• Where to buy replacement parts? I usually get them on eBay. They're much less expensive than retail shops, the quality has never failed me, and the selection is second to none.
  
• Don't forget: You're voiding your warranty by doing this. This is often not a problem since you definitely wouldn't be doing this repair yourself if it was still covered under warranty, but it's worth repeating for you adventurous types.

Good luck with your laptop repairs!