# [SOLVED] My computer won't stay on?



## skootterk (Jan 1, 2011)

This is my first build, and I am a little stumped as to what could be causing this. At first boot the motherboard runs for a second then shuts off, then after 6 seconds or so, it turns back on, runs for 20 seconds then shuts back off. After another 6 seconds it turns back on for 20 seconds then shuts back off.. I've taken the motherboard off the case and disconnected from all the peripherals and it still does the same thing. How can I tell if it's the CPU, the motherboard, or the PSU?

My build:
Motherboard: Gigabyte P55A-UD3
CPU: Intel i5-650
PSU: Raidmax Blackstone RX 700AC (700W)
Memory: Mushkin 2x4GB 1333
Video Card: GeForce GTX 465
Hard Drive: Western Digital 1TB SATA3
Optical Drive: ASUS DVD-RW
Case: NZXT Apollo Black

First post, I assumed this is the category for this thread.


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## Tyree (May 10, 2009)

*Re: My computer won't stay on?*

First thought would be the low quality RaidMax PSU. 
I would suggest a bench test with a minimum 750W (preferably an 850W for the GTX 465) PSU.

Remove EVERYTHING from the case.
Set the motherboard on a non conductive surface. The motherboard box is perfect for this. DO NOT PLACE THE MOTHERBOARD ON THE STATIC BAG! It can actually conduct electricity! 
Install the CPU and heat sink. 
Install 1 stick of RAM.
Install the video card and attach the power supply connection(s) to the card if your card needs it.
Connect the monitor to the video card.
Connect the power supply to the motherboard with both the 24pin main ATX Power connection and the separate 4 or 8 pin power connection.
Connect power to the power supply.
Do NOT connect ANYTHING else. Make sure you have the power connector on the CPU fan connected.
Use a small screwdriver to momentarily short the power switch connector on the motherboard. Consult your motherboard manual to find which two pins connect to your case's power switch. Then touch both pins with a screwdriver to complete the circuit and boot the system.

If all is well, it should power up and you should get a display. Then assemble the parts into the case and try again. If the system now fails to boot, you have a short in the case and need to recheck your motherboard standoffs.

If the system does not boot after this process, then you most likely have a faulty component. You'll need to swap parts, start with the power supply, until you determine what is defective


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## skootterk (Jan 1, 2011)

*Re: My computer won't stay on?*

I took the motherboard out of the case, disconnected all the peripherals till it was just the motherboard, CPU (w/ fan), one stick of RAM and the PSU on a non-conductive surface, and got the same problem. Is there anyway to tell which part is causing the problem? I think I need to RMA a part, just not sure which one.


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## Tyree (May 10, 2009)

*Re: My computer won't stay on?*

Remove all the RAM and try to boot. If the Mobo is good you should hear a consistent single beep from the Mobo speaker. Substituting parts, as described in the last paragraph of the Bench Test, is the only way to determine what part is defective.
The RaidMax PSU is the first suspect and should be replaced with a quality unit anyway.


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## skootterk (Jan 1, 2011)

*Re: My computer won't stay on?*

Thanks for your help, I figured out the problem, just a first time builders noob problem. I had never connected the monitor to the video card, so on start up it would tell me to push delete key to start up BIOS, without the monitor I could not see this message. It would wait 15 seconds, but with no OS and without being told to enter BIOS, it would just shut down. I connected the monitor, saw the message, entered BIOS and configured it for OS installation. It's now up and running! 

I will look into other PSU options, I was unaware of Raidmax's reputation.


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