500w isnt bad if you dont have 10 hdd's or a massive video card(s). I have a 585watt and at once I was running 1 IDE hdd 1DVD burner, 1DVD/CD combo 2 Sata Drives, a dual core intel processor, and Dual Sli 8500's but they were oc'd a little and had giant fans on them, and it ran fine. Just remember to read reviews and make sure that the processor really lives up to 500w. as far as a card, like i said, i have a 585watt and right now i have just 1 9600GTX and it runs fine and probably would on a 500 watt as well.