My computer shuts down after about 3 mins?

13abie

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Sep 12, 2009
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Every sort of 3rd time I switch on my computer the screen works. I know for a fact that the screen is not faulty as I tested it in other computers

Also after about 3-5 min my computer just shuts down randomly

Zalman 750w power supply
Intel core i7 920
6gb ddr3 ram
8800gt

Why am i having power issues
 

13abie

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Sep 12, 2009
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I tried those

Zalman 750W ZM750-HP Power Supply Mpdular SLI Quad +12V (ZM750-HP

EVGA X58 SLI LE Version - 141-BL-E757-TR (141-BL-E757-TR)

I built this computer yesterday and there is no OS installed
 

13abie

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Sep 12, 2009
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Now the moniter wont register at all.

When I start up the computer there is a long beep followed by 2 short beeps
 

Paperdoc

Polypheme
Ambassador
One beep code table I found say for Award BIOS (which your board has), 1 long + 2 short beeps "Indicates a video error has occurred and the BIOS cannot initialize the video screen to display any additional information".

Check your manual, pages 33 and 66-72 for how to read 2-digit error codes on the mobo debug LED readout.

One thing to check: see manual p 52, configuring the initial video display. You must set here in the BIOS whether your video card in is a PCI or in a PCIEx slot. they are not the same - set it wrong and the BIOS cannot find your card.