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I just built a new computer and when I first powered it on I got a continuous beeping which according to the manual means a power failure. After moving the voltage switch to the left a little I was able to get the beeping to stop. Even after the stopping though the CPU fan doesn't spin, and there is no display on the monitor. All the other fans and lights come on in the computer though, the DVD drive is working and ejects the tray, and the hard drive sounds like it spins up.

Has anyone seen this before and know what is wrong or what has failed?

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I think you kind of answered your own question, does sound like the PSU is shot, or not supplying enough juice. – Kez Mar 6 '10 at 23:32
up vote 3 down vote accepted

Probably your PSU has failed (a very real possibility even if it's new) or if you have dedicated graphics the card may be defective - try reseating it.

Because of the way that PSUs work in 'rails' it can provide enough power down a dedicated 12v line to drive fans while not suppling enough power down a different rail to power the motherboard and CPU.

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We had an electrical storm last weekend here. I had about six computers that all died in the storm, half of them exhibited this exact behavior. All of them were fixed by replacing the PSU, although one computer required that I chkdsked the hard disk as well. – James Watt Apr 23 '10 at 3:24

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