Boot issues after thunder storm

Boot issues after thunder storm

The village where I live was sat under a thunder cloud for most of Friday, and we suffered a few power fluctuations (specifically, what seemed to be split-second outages). When I got back home from work, I found that my PCs had shut down during one of these outages. When I went to boot one of them back up, I couldn't get anything to display on screen, nor did the boot seem to complete correctly. I tried a number of things - unplugging different bits of hardware, swapping graphics adaptors, etc. - to no avail. I thought I was looking at a fried motherboard or CPU. Power seemed to be distributed correctly to the peripherals (the drives all appeared to be working) so I figured it couldn't be the PSU. Eventually I unplugged it from the mains and left it overnight (approx 12hrs unplugged). I tried it again this morning, and it booted up correctly. Woo-hoo!

Asked by: Guest | Views: 291

Total answers/comments: 1

Comments display order:

Guest [Entry]

"If you have a brown-out, you may lose the power to one of the power rails, but not the others. This could cause it to appear off, even though parts of the power supply are still on. This could especially be the case if you have a power hungry Video card. It would pull all of the power off the 12V rail, but the CPU, doesn't generally need the 12V rail to actually function. If this is the case, you might see the Num-lock light on your keyboard.

I've had the reverse problem, where the 5V rail lost all power, because of a faulty USB cable. So the computer wouldn't respond, but the screen still looked the same, because the Video card still had plenty of power.

If you suspect this as the problem, unplug it from the wall, and press the power button. This should be enough to empty out the capacitors.

I think you wouldn't have had this problem, if you had it on a UPS."