TL;DR version: How can I figure out exactly what drivers I need, when I don't know what the hardware is?
So here's the scoop:
My wife owns an Acer Aspire 5100 laptop. At least, that's what it says on the bottom of the computer. This model doesn't seem to exist on the Acer website, and even when I google it, I get references to different specs than this one seems to have. This one came with Vista and 1 GB of RAM, for example, and I see a lot of references to XP and 512 of RAM.
The problem begins with the computer dying. It's not a great machine anyway, and in fact it doesn't even run at 1 GB of RAM because the onboard graphics card uses some of it, so Vista lumbers like a beast, things have been getting slow, crashing, etc.
"No problem!" says I. "I know computers! Also, I will install a better OS on your computer!"
So... I manage to install Windows XP SP 3. Lovely... except I forgot about drivers. Now, I had a lot of trouble getting stuff installed, so in this process, I have totally reformatted the HD a few times. There is nothing there if there once was some sort of backup partition. I even installed Ubuntu briefly, which actually worked fine, but my wife didn't like it, so now XP is on there.
XP installed fine at this point. It runs fine. It just doesn't recognize a lot of my hardware. Namely, the graphics card and my wireless card. The problem is... I have no idea what they are. There's no receipt, no sales record, and nothing to be found on the website. I have truly no idea what sort of wireless card, what sort of (I think) onboard graphics, what sort of anything. If I did, I could hunt for drivers... now I'm kinda stuck, and XP doesn't think this computer is capable of wireless.
Strangely, Ubuntu had none of these problems. It got online instantly.