Power Supply Problem?

January 2, 2008 11:12 AM

Power supply problem? A few weeks ago, when high winds hit the Oregon coast, my house lost power and my PC shut down. When it was restored, my computer wouldn't restart. So, I toggled my surge protector on and off, tried again, and the computer started. Then I unplugged the surge protector and waited out the storm. No problems until yesterday...

...when I tried to start my computer and it didn't didn't turn on. So, I toggled the surge protector and the computer started when I pressed its switch. All of the other items that draw power from my surge protector had power. This morning, I started up the computer, Windows 2000 loaded, and then it shut down for no apparent reason, and would not restart. Again, I toggled the surge protector on and off, and the computer started when I pressed its switch. Does anyone know what's going on here? Does this pose a danger to my data?

posted by partner to computers & internet (7 comments total)

Sounds vaguely similar to what happened to one of our computers after there was a power surge. Problems booting, random shutdowns, etc. I replaced the power supply, and everything has worked just fine ever since. The danger to your data is that sudden power loss can cause data corruption, and can render the system completely non-functional if the wrong files get corrupted. Changing out the power supply is pretty easy, and comparatively inexpensive.
posted by Lokheed at 11:32 AM on January 2, 2008

Sounds like your surge protector may have failed, or is about to fail. And it probably only poses a moderate threat to your old data- assuming you don't let this problem go on for much longer - but your new data may be impacted if it goes out before a save, etc. Your computer's power supply could need to be replaced, but I'd start with the surge protector.

- Did you plug the CPU back into the same socket on the S.P.? It could be a specific problem with the socket. If this doesn't fix the problem, then...
- Can you swap it out with another S.P., or get a new one, and see if the problem goes away?
posted by uaudio at 11:32 AM on January 2, 2008

I have also heard from a relative that had this happen. Replacing the power supply worked.
posted by Pants! at 12:20 PM on January 2, 2008

This is often the behavior of bad capacitors (kinda works sometimes, doesn't others). When you say your PC doesn't turn on, is it not getting any power at all? If that's the case then I'd agree with replacing the powersupply. If however the fans are turning on but you're getting no boot up screen it's possible the issue could further up the troubleshooting chain (motherboard or cpu next). Since this appears to be a power issue your data should be fine for the most part.

If you feel adventurous and want to inspect for blown capacitors, they are the little battery looking things on your motherboard (don't take apart your powersupply unless you detatch it completely and take precautions to avoid electrical shock..as a charge can be stored for several days..you might be able to shine a flashlight in the vents to see the capacitors however). Mainly you'll want to look for the symptoms in the linked image above...bulging caps are the most frequent sign they're going bad.

Good luck!
posted by samsara at 1:01 PM on January 2, 2008

In answer to samsara, there is no power getting to the computer. So, as you say, the power supply is suspect. But, I don't understand why toggling the surge protector fixes the problem. If the circuit isn't completed in the power supply, no electricity is flowing in the wire even when the surge protector is on. What changes in the power supply?
posted by partner at 2:50 PM on January 2, 2008

Seconding all three suggestions (!) above. The mobo should be inspected first. If you spot a blown cap DO NOT turn your machine on again until you replace the board. There's no sense destroying your memory or processor if you've identified the problem. If not, a new power strip is like $3 at your local box store and a new power supply is <>
Good luck. Intermittent errors like that are very hard to trace out!
posted by datacenter refugee at 3:12 PM on January 2, 2008

My best guess is that toggling the surge protector releases the charge. With most ATX powersupplies, even when you "shut down" there is still a small amount of charge going through the powersupply and connectors on the MB for alternate power-on methods (eg. power on by front button, power on by keyboard/mouse, or power on by Wake-on-lan.) Do you have a switch at the powersupply itself? You could probably get the same thing to happen there too as that will cut off the power completely to the MB.

As datacenter refugee points out this is usually tough to trace out as it could be either the powersupply or the MB. Replacing the powersupply is definitely the easier start (buy it from Circuit City or a similar outlet...return it if it doesn't fix the problem, then get a MB replacement).

This is all assuming the PC is out of warranty of course, as the absolute best option is to snag your HD out and send it back to the manuf. for repairs :)
posted by samsara at 7:03 PM on January 2, 2008 [1 favorite]