Yeah jsc basically said it. I really depends what else you are running, I mean if you have that cpu using onboard graphics 1 optical drive and one hard drive you could run a 300 watt psu all day, but if you are using a discrete graphics card a couple of hard drives and optical drives, overclocking, SLi, CFx, etc. you could need anything from 500w to 1000w.
So to answer your question... Tell us what else you want to run in the system.
thanks for the response people!! i really appreciate it. well i've got a graphics card (1gb nvidia geforce 8500gt), a dvd writer, 1 hard drive and i plan to buy another hard drive. I'm using this computer for graphic designing, video editing and gaming, i use it almost 24/7. so this means i should get a 1000w psu?
No, you do not need a 1,000 watt power supply for a system with one 8500GT video card. A 1,000 watt power supply is designed for a seriously overclocked gaming system with multiple video cards. Your power requirements don't even come close to a high end gaming system like that.
The general rule of thumb is a high quality 500 to 550 watt power supply with sufficient current (amps) on the 12 volt rail(s) can easily power a system with any single video card made.
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