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Greetings SU,

My PC just stopped functioning properly after it has been running fine for nearly 2 years. When I turn it on, all of the case fans turn on, and I see the case LEDs light up. My Graphics card doesn't look like it's driving the monitor - I can see the fan on it try to spin up, but it stops after running for about 5 seconds. It then tries again, spins for 5 seconds, and then stops. It's a PCI-E card, and it has a power connector going to it.

I don't hear/feel my hard drives spin up either, which makes me lean towards it being a power supply issue, but I'm thrown off by the fact that the fans and case lights are working fine. Can this happen with power supplies? I have this OCZ GameXStream PS. I've seen on another answer that there are power supply testers, but I don't want to spend more than I have to. I might end up getting one anyway since I do plan to build again sometime.


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Thanks to all - it was the PSU - scared me at first seeing as the machine didn't turn on when I hit the power button.. had a bad connection somewhere. – SB01 Sep 3 '10 at 0:41
up vote 1 down vote accepted

Hop down to the local parts shop and pick up a PSU for $50, install it outside of your case and see if your problems are gone. If not, try using on-board video and removing your card, or replacing it.

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If the system doesn't show the BIOS and you feel that the hard disks aren't spinning then it sounds like power supply failure.

Power Supply Failure Symptoms More often then not, a power supply will just quit working instead of warning you that it is about to kick the bucket.

Here is a list of common power supply failure symptoms:

  • There are strange noises coming from the back side of the computer where the power cord plugs into the power supply.

  • Nothing happens when the computer power button is pressed. Sometimes a light may flash or flash continuously in the front of the computer or on the back of the power supply.

  • The computer turns on for a few seconds and then turns off. (Sometimes this is unfortunately associated with motherboard failures.)

  • Computer turns on for a while, but when games or other applications are using the computer steadily, it will turn off or I get a blue screen.


If you were already planning on purchasing a power supply, give it a shot. If it still doesn't work then trouble shoot the video card, however, if the system doesn't boot, there a possibility of Motherboard failure.

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At this point a power supply tester might be worth the money (about $35). Power supplies produce multiple voltages and if the right one went bad (say the +5 volt), you might still get fans (+12 volt) but not much else. I would think the case LEDs would be +5 so that's an argument that says PSU might be working and thus pointing at the graphics card being the culprit.

A good PSU tester will have plugs that match connectors on the motherboard, PATA hard disks/CDS, floppies, and both 4 and 8 pin motherboard/GPU plugs. You're going to have to either know or research what the appropriate voltages (lit leds) should be for your system.

If you're a gamer (I read that to mean you buy expensive PSUs) then the tester might save some $$$ in the long run.

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are the expensive power supplies worth it? if it's the PSU, then I'm clearly going to have to say no.. – SB01 Aug 31 '10 at 12:13
If your components suck up a LOT of power then it's probably going to be expensive. You don't want to be underpowered because that puts your entire system at risk. Buy a PSU from a reputable company that consistently gets good reviews. Getting something rated about 30 to 50% more than the current MAX draw on your system is probably a good idea. Try not to buy features you don't need. I see excellent 650 watt power supplies on sale for $65 all the time. If you need much more than that be prepared to pay more. – hotei Aug 31 '10 at 14:11

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