PS problem???

[HmgStrider]

Hey guys i'm not sure whats wrong with my computer. Sometimes my computer won't boot up. It seems like the computer is booting up but nothing happens to the monitor it just stays black. At first i thought it was a bad motherboard since alot of pple in the forum said it was the board so i bought a new board. It worked fine then i put a new heatsink fan on the volcano 7 and the problems all came back. It wouldn't boot up so i figure the only problem left was the PS. I unplugged my one of my cd roms and my zip drive and it booted up. So what do u guys think the problem is??? I think its the PS, what would be a good PS to get. The current one i'm running is 320watts but its not approved by amd. Whats a good power supply for a 1.4 266fsb atlon with a gigabyte 7vtxe board. I'm also running dvd, cdrw, zip, hd, floppy. Give me a suggestion, i'm looking at the enermax PS 350 watts amd approved for 1.4 let me know what u think.