Not much of an assessment. I have a BFG 550, running an overclocked Q9400, BFG gtx 250, 5 HD's, 8gb or ram, DVD, and 4 120mm fans. Runs like a champ. Your biggest draw will be the video card. You could probably run on a good 400 watt.
Look for quality in the PSU. I like Antec, although my other one is going in for RMA.