Just put together a new PC for a mate MSI k7n2 delta mo'board XP3000+ (barton) 512mb ddr pc3200 crucial ram msi fx5600 maxtor 120gb hdd Antec case and 350watt psu All of the above are new components The problem i have is that on powerup it mostly powers up, beeps once (short) and then powers down the only way i can get it to repower up is to unplug from the mains and then plug back in. If left powered off for a while it powers up long enough to get into the bios or boot from the windows xp cd and perform its systems check and then it powers down again. (roughly one minute b4 powerdown at best) I've checked the usual stuff , cpu temp is 44 degrees c ,case is ambient temp (from bios), tried with just the basics (gfx,cpu and ram) with no change in the problem. Powered up the psu by shorting the atx connector between the green wire and earth and it runs the 2 x120 mm and the cpu fans fine, and i've been through the stickied pc diagnostics thread I have however noticed a few niggly little things about the psu like the fan on it is mounted the wrong way round (it sucks air from the back of the case into the psu , now in my eyes this is wrong because every other psu i've ever used has the fan exhausting not as an inlet) What I need is some suggestions on the problem and possible solutions, We're going to try swapping out the psu 2moro to see if that makes a difference and also the ram when i get mine out of my machine . Would a faulty PSU cause these problems or is there any other possibilities?