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Hardware, History & PC 
The Secret Guide to Computers (R. Walter) A History of Computers
How Computers Work (Gill Pratt) Computers Systems (Luis H. Rodriguez)
Basic Computing Using Windows Upgrading & Repairing PCs, 8th Edition [Mirror] [Mirror]
How Computers Work: Processor and Main Memory (Roger Young) [PDF]
Computer Basics: an Overview of Computer Hardware Hardware Book [Mirror] [Mirror]
A History of the Personal Computer: the People and the Technology (Ray A. Allan)
Build Your Own PC The PC Guide
How It Works...The Computer Visual Computer Hardware Guide