How many watts am i going to need

[runboyrun]

i will be purchasing a radeon 5770 1gb. a core i5 750 or 760. 4 GB of ram . I will be overclocking this system as well.

 

[delluser1]

550 watts 40+amps, will leave room for doubling up the card.

 

[iam2thecrowe]

something around 500w by antec, seasonic, corsair will be fine. you could go less to about 350-400w, but its good to have more so there is no real strain on the psu and leaves room for future upgrades.

 

[4745454b]

Roughly speaking you'll need around 100W for that GPU and your CPU. Toss in another 50W for your board and other devices and you're looking at 250W for your system. This needs to all be available from your 12V rail. If you want to CF, you'll need about 350W.