Thursday, August 28, 2008

My Computer is Freaking Me Out (Little Help, Please)

The PC that seems to have a ghost in the machine.

About halfway through my evening lesson, I started to hear what sounded like a tapping noise behind my television. It was raining outside so I thought it was some sort of referred sound from water dripping or that there may possibly be a leak such that water was dripping between the walls.

About 10 minutes later, the old PC that I keep under the television spontaneously turned itself on. It has a very loud fan so it's impossible not to notice that it has revved itself up. I mentioned it to my student and made a joke about a ghost turning it on. I reached over and turned it off. Very soon thereafter, I heard the tapping again and this time I noticed that the power light on the USB speakers attached to this particular PC was flashing and then the PC turned itself back on again. The second time, I let it go since I didn't want to disrupt the lesson. As soon as the lesson was over though, I unplugged my self-starting PC.

I've never had this sort of problem with a computer before, but I have to imagine this isn't good. This particular PC is about 6 or 7 years old and I'm guessing there is some sort of power supply failure going on, but I'd really appreciate any advice or feedback from others who have more knowledge of the electronics of a computer and what might be causing this.

I had planned on re-formatting this computer's hard drive because it had been acting wonky when connected to the television (which is all it does now). It was having a weird crash where the T.V. would blank out and we couldn't get the screen back unless we restarted. I thought it was a software issue, but now I'm starting to wonder if it was something else.

So, is this computer ready for the happy hunting ground?


Roy said...

That happens with my PC as well. I will put it into sleep mode in the morning and watch it go off before leaving for work. But when I get home it's on. When I shut it down properly it never happens though.

Maybe the ghost wanted to check his mail?

'badmoodguy' is mike said...

One thing to check is go into the BIOS setup of the computer and see if there is an option in there regarding "State after power loss" or something like that.

Power supplies on modern computers are not like the ones of old. The power supplies are constantly on and are constantly powering something on the motherboard. If the motherboard detects that the power has been removed because the power supply lost mains power (or thinks it did) then a flag set in the BIOS can control what happens when power returns. There are generally three settings: Last State, On and Off. If the setting is in "on" then if the power is removed and returned, the computer will automagially switch back on. This is usually used for servers that take care of themselves. If it is in "off" then the computer will stay off whether it was on before or not. If it is in "Last State", the computer remembers whether it was on or off, and will return to that state when the power is brought back on.

Many computers, however, don't have this setting so it could be a long shot.

Another thing to try is see if the manufacturer has a BIOS update for the PC.

Otherwise, it could be a wonky motherboard or power supply or power button connector. Usually the power supply is flaky. All that is required to turn on the PC is shorting a single wire from the power supply to ground. So, if there is something in the supply or on the motherboard that is faulty and shorting the power on pin, it could start the PC.

Hopefully it is a standard PC power supply and not a proprietary style like some manufacturers have a penchant for using. If it is a plain-jane, you should be able to get a decent one for about $30 US.

Love the Python poster, BTW!

Orchid64 said...

Roy: Stupid ghost should get his own computer!

Mike: Thanks very much. I had a feeling you'd come through for me! Your explanation really helped and I appreciate that you took the time to type all that out. I'm going to look into the BIOS situation as soon as I have some time. I'm hoping that that was all it was. I don't know anything about the power supply type but given the age of the computer, I'd almost certainly just let it die than go to the trouble of tracking down a power supply (the machine is from the U.S.).

The Python poster is a favorite. Since I took the picture, I fixed it properly in the frame (you may notice it slid down, now it's centered). I wish we could find more like it, but they're exceptionally rare in Japan!

the melodic news said...

Roy, it's not a ghost. It's the little people that live behind the radiator that have parties while you're out.

Orchid64 said...

I think I'd rather have little people behind the radiator than underpants gnomes. ;-)