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As described in the title, my desktop system will boot properly and at its usual speed, will run normally for between 3 to 7 minutes--in my observations thus far, 7 minutes is the longest and a significant outlier, it usually runs for 3-4 minutes--then, without any apparent warning, the signal to my monitor will be cut, as will the signal to my speakers. I can discern no response to any input via mouse or keyboard, and attempting to switch the system off with the front power button does nothing. I've let the system to run for up to 15 minutes in this state thus far, with no observed change or response. I've had to resort to using the power-supply switch to power the system down and reboot.

This has only started happening today. Specifically, the machine was operating as per usual this morning. I put it in 'Lock' mode, then went for a walk. I returned roughly an hour-and-a-half later, and the system had powered down. I initially attempted to turn it back on with the front power button, but this had no effect. I switched the power supply off and on, and it booted successfully, but I heard a 'snapping' sound and caught a whiff of an unpleasant scent. I shut the system down through Windows, and checked for smoke or any sort of visual indicator, but the inside of the system looked fine as far as I could see, albeit dustier than usual.

The system had not been dusted out in roughly three months, as opposed to my usual monthly cleaning, so I switched off the power, unplugged it and cleaned the system out with compressed air. After waiting for a short time and hooking everything back up, I switched the power supply back on and booted the system up. Ever since that boot attempt, it has been exhibiting the problem behavior described above.

Prior to this, the system had only exhibited one consistent problem behavior, which was occasional freezing and crashing--activity independent, mind you--that appears to be attributable to the faulty SSD in my system. When booting off the HDD, those problems never occurred. Otherwise, the system has been healthy and responsive prior to today.

For detail's sake, in case it helps, the hardware inside the box:

  • Mobo: msi 870A-G55
  • CPU: Phenom II X4 955 Deneb
  • PSU: Antec Earthwatts
  • EA650 SSD: OCZ Agility 3 120 GB
  • HDD: Samsung Spinpoint F3 1TB 7200
  • RPM RAM: G Skill Ripjaw Series 8 GB (2 x 4GB) x 2
  • GPU: GIGABYTE GV-R577D5-1GD-B Rev2.0 Radeon HD 5770

Running Windows 7 Home Premium 64-bit.

The system is currently running in the unresponsive state.


Having purchased and installed a new power supply, the same problem persisted. I went ahead and tried switching to the HDD as the primary boot drive just on the off-chance it was some SSD failure behavior, but again, the same problem persisted. I took the whole system apart and inspected every component closely, again finding no signs of physical damage anywhere on any piece of the circuitry. On a whim, I decided to fire the system up with the side panels off and watch for some sign of activity on the boards that corresponded to the strange behavior.

Sure enough, an indicator labeled OC GEAR1, which resembles a speedometer, goes from off to red at the instant the problem occurs, with a blue LED near it also activating at that moment. So I booted to the BIOS, and I seem to be able to muck around in here without the error taking place: it has been 45 minutes at this point with no problems. Now the issue is that I'm not really sure what I'm looking for. I do notice that the CPU seems to be running a little hot (58 to 60C), but otherwise I'm at a loss.

Oh well, at least I only spent $25 on the PSU.

share|improve this question
Can you see any burn marks on your motherboard, power supply, or markings on cables? Sounds like something shorted on the motherboard. Replacing that would be the quickest way to determine if something else is the cause (or is also the cause). If you think your SSD is unreliable, use the HDD then as the boot. – LunaMezza Jul 30 '13 at 19:38
A pop, acrid smell, and no use of the front panel power button sounds like the PSU is going for the long dirt nap. Although it may be something other than this, it would be my suggestion to find a friend who wouldn't mind letting you use theirs as a test to confirm or eliminate that the PSU is the issue. – Carl B Jul 30 '13 at 20:00

Well, that sound and smell make this easy to diagnose. It's a hardware issue, most likely a capacitor failed. If you take the side off the computer, visual inspect each of the circuit boards. What you're looking for is something that looks scorched or burnt, and specifically a blown capacitor.

Capacitors are typically cylindrical (sorta look like tiny soda cans). The top of it would be bubbled/cracked, and there may be some leaked stuff that smells pretty bad.

If you don't see that after investigating ALL of the circuit boards, more than likely it's your power supply.

The only way to fix this is to replace whichever part failed.


Based on your symptoms, you're going to cause even more damage if you keep fiddling with it like you have been, and you may not be able to see that damage.

share|improve this answer
I saw neither scorching nor any damaged capacitors on my circuitry. I will try to test my power supply in another unit soon to confirm your suggestion. Thank you. – user242007 Jul 30 '13 at 23:48

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