Reddit reviews Upgrading and Repairing PCs (20th Edition)
We found 4 Reddit comments about Upgrading and Repairing PCs (20th Edition). Here are the top ones, ranked by their Reddit score.

Used Book in Good Condition
This book I highly recommend, its currently on the 19th edition with the 20th releasing shortly. It covers the details of every single piece of pc hardware in depth.
Upgrading and Repairing PCs (20th Edition) by Scott M. Mueller
If you're interested in the technology of, I strongly suggest "Upgrading and Repairing PCs". Here's a link to the latest edition on amazon.
I think it's exactly what you're looking for.
http://www.amazon.com/Upgrading-Repairing-20th-Scott-Mueller/dp/0789747103/ref=sr_1_2?ie=UTF8&qid=1318482723&sr=8-2 Try that. I've had two editions of it: dunno what I did with the one from 10 years ago, but the one from 3 years ago I gave to my brother.