In Upgrading and repairing PC's, Scott Mueller explains the basics of assembling and repairing PC hardware (the physical systems). Though he does go into the basics of upgrading system bios and system restoring, he sticks to the hardware the whole way through.
I liked the attention to detail on handling the newer processors and equipment, but i don't like that he left out a few tricks that you need to know for the older ones. However the book is based for newer computers so leaving out old, obsolete systems, is OK if it's just repairing your own PC.
I also like the included CD witch gives an inexperienced reader / mechanic an actual look at how to install and handle the raw hardware(mother board, ram cards, processor, ext.), before they try installing it themselves.
Over all he covers all the newer, and older systems, enough for the book to be well worth the effort to read.