I'm not exactly sure if this is an issue with the power supply or not, but hopefully someone here will know.

I'm building a computer for my girlfriend from spare parts, but the power supply and case are both brand new. It's running Windows XP and it turns on and boots properly every time...unless the computer decides it needs to "Restart".

I can easily shut the computer down completely, then manually turn it back on again with no problems whatsoever. However, if I choose to Restart the computer from Windows (or anywhere else, for that matter), the computer turns completely off, and becomes unresponsive. I can push the power and reset buttons all I won't, but it won't fire back up.

I know the computer has power because the power light on the motherboard is illuminated when the computer turns off, and I know that the power button works and is connected properly because otherwise I would not be able to turn it on in the first place.

This is a real head scratcher, and I definitely have no idea what could be causing it, but right now, the only way to make the computer boot back up after it shuts down during a restart operation is to unplug the computer from the power source, wait until the power to the motherboard has been drained (which is determined by looking into the case and watching the power LED on the motherboard dim, then turn off.), and plug the computer back in and press the power button. After doing this, it runs fine.

Any help in solving this problem would be greatly appreciated.

Thanks in advance,
-Kolby

welcome to PCHF

Was the Power-Supply a "came with the case" model -- or one you picked out ?

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The power supply came with the case. I'm typing this from the computer in question, so I can't open the case at the moment to tell you what kind of power supply it is, but I'm almost certain that it's a 350 watt power supply, and the components in the computer should most definitely not require any more than that, and everything seems to run fine when it's powered on.

350 Watts may be enough rated power for the hardware-- but from experience-- I can tell you that it is probably weak in other areas.
Very few case vendors put a decent Power Supply Unit in a case (without charging extra)
The load at bootup is at it's heaviest-- and if there's not enough juice, it would produce the exact symptoms you describe.
Power Supply Unit's are totally unregulated hardware-- so it's "buyer beware" (no offense intended). There is a LOT of junk being sold, unfortunately.

I could suggest a few good brands for you if you wish...especially since you are in the US-- lot's of selections.

I specify cases without a Power Supply Unit for exactly this reason, when I buy.

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I don't understand that though, because the computer starts up just fine otherwise and has no errors or [evident] abnormalities whatsoever; it's only restarting that is an issue.

But if it really is a power supply issue, then if you could, please list a few good vendors/manufacturers.

OK--
could I ask if you use the PC for any gaming-- have you tried any benchmarking apps? This would put the hardware under a bit of strain-- as a test...?
As I said above boot-up is the hardest part, otherwise. Once it boots it may have just enough to squeak by when operating at idle or just above it. Trouble is-- eventually it will cause problems, especially when you go to upgrade.

For vendors in the US -- Newegg.com is my usual vendor.

Newegg.com - Power Supply, Computer Power Supply, Uninterruptible Power Supply, DC Power Supply, PC Power Supply, ATX Power Supply
The only other way to be certain is to take the unit to a PC repair shop & have it tested with meters under load.

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The computer will only be used for browsing the internet or for word processing, e-mail, etc. Nothing strenuous (like gaming, video editing, etc.)

I've dealt with newegg before, and actually thought of buying a power supply from there, but I bought the case and power supply together from a local computer store.

I have not done any gaming or benchmarking on it, and it more than likely will never be upgraded. Could you recommend a good benchmarking program for me to use/try?

Mom and Pop shop ? Or big chain store?

Download Fresh Diagnose 7.76 - Analyzes and benchmarks different kinds of hardware, such as CPU performance - Softpedia

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