I'm starting a new build for around £650 and have pretty much decided to to go with...
Intel E8400
1 TB hard drive
4 gb ram 4-4-4-12 (800 mhz)
Asus P5Q Pro
Creative SoundBlaster X-Fi Xtreme 7.1
but I can't decide what graphics card to go for. I want to spend about £120 on it and wondering what I should go for. I play a few games and may want to overclock if that helps.