I can guarantee that I would annihilate you on cod4 with a controller if you had KB and Mouse and as stat said you spent probably 3-4x the amount of a 360 for your "PC Specs"
also:
http://www.smarthouse.com.au/Gaming/...7L7H2R4?page=1
so Zzzzzzzz
regardless as stat said...everything is downloaded on that system anyway