Gaming card (dont get a cheap one. If u wanna game get a good one)
Sound card(same with gaming card. Better sounds=easier to detect)
Intel quad core with 3ghz or higher.. doesnt have to be I7 but if it is great
Decent Cpu Fan(cooler the cpu the better)
PSU with 600watz+
Case with couple built in fans
HD with 7200RPM+... get something around 500gb if not too many games, 1tb if ure gonna have LOTS of games on...
If u dont, get a nice screen and a mouse. I dont care much for keyboard in my opinion