well, i want to get a newer video card, another hdd, and a dvd burner for my dimension 8200, from what i've read, this model can use any old atx psu, is this true? if it is, what do you recommend i get? im looking for a fairly cheap psu just to power a 6600 gt, dvd burner and 2 hdd's. Finally, how hard is it to replace a psu? im basically a noob, i have some knowledge but not much, any help is greatly appreciated, thnx