Member Avatar for Xythan

I just made my first attempt at building my own computer yesterday and since then have not been able to get it to start up. I know everything is connected properly. I've tried getting it to start up outside of the chasis as well, but the same thing happens whether it's inside or out. Anyway, here's the problem. I currently have only the power supply, processor with heatsink and fan, one memory stick, and a video card connected to the motherboard and the chasis connection in their proper places. When I press the power button, the fans on the power supply, the processor and the graphics card spin for about five seconds, then everything shuts down. Then, without me touching anything, everything will start to spin again for 3-5 seconds and then shut down again. This process repeats itself until I turn the power source off. Any ideas? I've been searching online for at least four hours and have found similiar questions but nothing that really matches this. Thanks.

~ Xythan

- MSI P965 Platinum mainboard Intel 965 Express chipset bassed
- VGA XFX 7900GT 256M PVT71GUQF3 R
- MEM 1G|COR 240P TWIN2X2048-6400C4
- PSU TT|W0104RU 650W RT

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  • Latest Post Latest Post by maxup

Dani AI

Generated

A brief, focused troubleshooting plan tied to points already raised by , and .

Short power-on cycles that stop and restart usually mean the power supply is tripping (overcurrent/short protection) or the motherboard is being shorted when certain power rails or cards are attached. The pattern where the PSU will run alone but cycles when the board or a component is connected narrows the fault to either a short/ground on the board, a failing component that draws a fault current, or a bad PSU rail.

Recommended steps (in order):

  • Run the board completely outside the case on a nonconductive surface, removing all screws/standoffs not required. Inspect underside and around the CPU socket for stray metal, bent pins or solder splashes.
  • Recreate a true minimum test: motherboard + CPU + cooler + single RAM module in the correct slot + required PSU connectors. Leave everything else disconnected. Use the board manual to confirm front-panel and power connector orientation.
  • If it still cycles, swap in a known-good PSU or use a PSU tester. If the system stays up with the alternate PSU, the original is suspect (as suggested).
  • If the system runs with PSU but fails once the GPU or a particular power lead is connected, test with an alternate GPU or try onboard video per to isolate the card or the PCIe slot. Also test by disconnecting GPU auxiliary power to see if the fault goes away.
  • Check front-panel wiring and the power switch. Temporarily short the power pins on the board with a screwdriver to rule out a bad case switch or incorrect wiring.
  • Watch for motherboard debug LEDs or beep codes and look for damaged caps, burnt areas, or unusual smells.

If none of these isolate the fault, the motherboard itself (shorted VRMs or damaged traces) is a likely candidate and should be inspected for physical damage and considered for RMA after verifying the PSU and GPU are good. Electrical safety and ESD precautions are essential during all tests.

Member Avatar for Xythan

Ok. I've done some more testing and I've found that as long as the power supply isn't directly connected to the board it will run continuously. I plugged it into my graphics card and the fan spun, but when I had the graphics card plugged into the motherboard it went back to its 5 second routine. Same would happen if I added power to the processor.

Member Avatar for mechbas

If you've an on board vga conn. try that or a more generic adapter. check your book f/a jumper setting. what does it do w/o the card?

Member Avatar for maxup

I just made my first attempt at building my own computer yesterday and since then have not been able to get it to start up. I know everything is connected properly. I've tried getting it to start up outside of the chasis as well, but the same thing happens whether it's inside or out. Anyway, here's the problem. I currently have only the power supply, processor with heatsink and fan, one memory stick, and a video card connected to the motherboard and the chasis connection in their proper places. When I press the power button, the fans on the power supply, the processor and the graphics card spin for about five seconds, then everything shuts down. Then, without me touching anything, everything will start to spin again for 3-5 seconds and then shut down again. This process repeats itself until I turn the power source off. Any ideas? I've been searching online for at least four hours and have found similiar questions but nothing that really matches this. Thanks.

~ Xythan

- MSI P965 Platinum mainboard Intel 965 Express chipset bassed
- VGA XFX 7900GT 256M PVT71GUQF3 R
- MEM 1G|COR 240P TWIN2X2048-6400C4
- PSU TT|W0104RU 650W RT

:idea: Hello Xythan,
have u tried changing the power supply or better still troubleshoot it by trying it on an other machine.If it works just fine,it could be rebooting because there is no 'OS' I had such a problem once only with me it would freeze & then go off completely.it worked just fine after replacing the processor with a slower 2Ghz.
hope this info will be of some help.

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