I bought a 25 dollar rosewill full atx case from newegg about a year and a half ago that came with a 350W atx psu. Somehow it ran for 1 year running a full atx pentium 3 mobo with 3 hd's and a combo drive, lan card, modem, video card, and a fan. Then it ran for about 2 months on my micro atx mobo with a amd athlon 64 3200+, 4 80mm fans, 1 120mm fan, 2 hd's, combo drive, modem, and a nvidia 8600GT. Somehow it ran all that time with no problems ever. So i went with a new Rosewill Stallion 500w psu, and it hasen't given me a problem yet.