So my computer was running a bit slow all day today, I didn't THINK much of it because it's not the most up to date computer. Anyway, I shut the computer down when I left for the night and when I came back not FIVE hours later and tried to turn it on the computer shut down on itself. I thought it wasn't a big deal because for about the past half a year in order to turn the computer on I had to hit the power button then the restart button three times, if I didn't do this it would shut down I would have to hit the restart button a couple times and then turn the power on and hit the restart button again. But I once I tried doing this nothing different happened. The computer turned on, made a noise and then shut itself back down. And I wasn't even able to get it STARTING any more. So I hit the power switch on the power supply waited for a moment till I heard a beep, I assume the beep is my power supply shutting down. So once it does that I turn it back on and it just starts to turn on for a few seconds and then shuts down again and I have to repeat this. I've also tried waiting several minutes before turning it back on.

I don't know hardly anything about computers, and any help I receive I truly appreciate.
Thanks.
-JoeP.S I dunno why it says "Unknown" for the OS but I'm running Windows XP.Unfortunately there is not one sole reason for this problem to occur.Your past start up procedures tend to indicate this has been a building issue for some time. The most common reasons for this type of problem are "heat". This can be due to a dusty computer interior restricting air flow or non operating (or improperly operating ) fans. It can also be a failing power supply unit. It can also be because of failed RAM. Other issue too can cause this such as component failure on the motherboard. Have you tried to determine if any of the above can be a cause? truenorthI have no idea how to check any of that other than the dust, that probably has a lot to do with it. I plan to get it all cleaned up a bit later today, as for the RAM I'm pretty sure its still good though I don't have the slightest idea on how to even check whether that's true or not. As for the power supply that's honestly what I was thinking it was, but once again I have absolutely no clue how to check that. I'm just hoping it's not the motherboard. I think I would cry if I had to replace it. x'/I am thinking the power supply too. I would test with a very minimal hardware start to see if you can at least get it to boot up and stay on. (Hard drive, 1 stick RAM, Processor, video). If so, then add the other drives and RAM and see where it doesn't stay stable. If you can't get it to boot with the bare MINIMUM then try ANOTHER power supply (hopefully you have a spare, even a junky one can help in testing). Note anything different when testing the spare, or between minimal hardware and full hardware. This can also help narrow down another component if it is not the PSU.

If nothing changes how it fails, it may be the motherboard. Usually when a motherboard goes bad, the computer doesn't start or stay on too long. So if you can get it to stay on for a while, you can breathe a sigh of releif that it probably isn't the motherboard. (Of note, motheboards aren't too expensive, probably $50-$75 depending on what you need).Start with the easy stuff 1st. Such as opening the case (you have NOT said so but i assume we are talking about a desktop as opposed to a laptop here). Be sure that you remove the power cord from the outlet and touch the chassis somewhere BEFORE you touch anything inside.Use compressed air to blow out any internal dust (hold or prevent the various fans from spinning as you blow in their vicinity).Once you have done a thorough job of that try the computer. You don't need to return the cover that was removed from the computer at this point. Watch very closely for any attempt of the fans to turn (even briefly). Note any fan that does not try to rotate and where it is. Do that and report back for the next step.truenorth