Turn on, damnit!

April 20, 2007 6:49 AM

YACQ (Yet Another Computer Question) - does this sound like a power supply issue?

My homebuilt computer stopped turning on. Over the past couple of months, it would randomly shut off and refuse to turn on for about an hour or so, and then act totally fine afterwards. There was no regularity about the shutdowns, which led me away from a heat issue (sometimes it would shutdown after an hour, sometimes after three days).

Two days ago, I turned off the computer and went to work. When I cam home, the computer wouldn't turn on. The power LED on the case, however, is blinking very rapidly at me. I've tried all the jiggery-pokery that used to revive the computer - unplugging it and letting it sit for a few minutes, switching the AC source switch back and forth from 220V to 110V and plugging it back in, but nothing has worked.

The power supply (300W) is about eight years old and powering an Athlon 64 with a pretty hefty video card, so my hunch is that I was just asking too much of the aging supply. Does this sound right?

posted by backseatpilot to computers & internet (6 comments total)

Power supply sounds right to me - should be a pretty cheap fix, anyway. It's probably worth a shot.
posted by soplerfo at 6:56 AM on April 20, 2007

Yup. Swap it for another one. If you've got a lot of hard drives or kick ass videocard get something bigger, I saw 450W selling for $18 around the corner.
posted by furtive at 6:57 AM on April 20, 2007

I had intermittent power problems related to power draw, heat, dust, and any number of other environmental issues. A new unit fixed me right up.

Due to the requirements from my video card, I picked up a whopper to give me some room to grow. CompUSA had a good deal on a product from BFG, which clocked out at 650W.
posted by thanotopsis at 7:25 AM on April 20, 2007

Make sure you have the internal speaker hooked up so you can hear if there are any POST error beep sequences when it fails to start. I'm with the others that the PSU is the likely culprit, as they're often the crappiest part of a computer and among the first parts to fail.
posted by knave at 7:42 AM on April 20, 2007

Power supply is a likely candidate, especially given the way you describe how it won't turn back on after an hour or so, and the age of the PSU.

If you've got a dead screen, fans running / hard drives spun up, and blinkenlights (no POST, but either keyboard lock lights or the LEDs on the front are flickering), it's generally either PSU or motherboard, and more commonly PSU in my experience.

One word of advice: don't cheap out on the replacement power supply. A cheap or underpowered one can lead to all kinds of stability problems, particularly with, as you say, a modern CPU and GPU on board. Go at least 300W on the replacement (maybe consider more, if you're going to be upgrading the box at some point), and a name brand (I prefer Enermax, but Antec and others make some nice ones. Check reviews.)
posted by theoddball at 7:51 AM on April 20, 2007

you might try hitting the power supply's innards with a can of compressed air; sometimes the gunk settles in the fans there and leads to weird overheating problems.
posted by jenkinsEar at 12:09 PM on April 20, 2007