Computer Organization and Architecture ebooks

JohnHennessy & DavidPatterson-4th Edition

http://www.ziddu.com/download/4013403/CA.pdf.html

Patterson Hennessy

http://www.ziddu.com/download/4930876/COA_Patterson_Hennessy.pdf.html

William Stalling  

http://www.ziddu.com/download/4667153/COA_WStalling_Part1.pdf.html
http://www.ziddu.com/download/4667287/COA_WStalling_Part2.pdf.html
http://www.ziddu.com/download/4667937/COA_WStalling_Part3.pdf.html
http://www.ziddu.com/download/4667848/COA_WStalling_Part4.pdf.html

Carl Hamacher and Safwat Zaky

http://www.ziddu.com/download/5628736/hamacher.rar.html