Power supply linked spontaneous shut down?

Hi there,

My computer has been shutting down randomly with no warning or error messages. Other experts on this forum suggested that I dust out the fans etc. I thought I got rid of the problem but a few days onwards it started again. It shuts down sometimes only a few minutes after I've turned it on. And when it does shut down, I cant turn it back on onless I wait a few hours and I'd have to turn the main power off at the back or at the wall.

Not sure what the problem might be. At first I thought it might be virus related but scans have come up clean..

Need help!

Thanks in advance.

Lorraine

 

Hello Lorraine,

I had spoken to to that expert about your situation and its my understanding that you have already blown excess dust from the CPU heatsink and cleaned things up a bit but the shutdown problem still remains. The two most common culprits in a situation like yours are excess heat or actual problems with the power supply itself. However, there are other potential causes which can produce the same symptoms so lets run through a few things.

Visually inspect all those little canister shaped things on your motherboard. You'll need a magnifying glass to do this right but make sure the top of each is not domed, but instead is a flat surface. These are capacitors and sometimes they will "give out ". Also check for any bulging in the sides or any evidence of a substance coming out of the top or bottom. Sometimes a darkening of the top seams are indicative of pending failure but you'll need magnifying glass to properly inspect these.

If they all look good, the next step I would suggest is to carefully remove your memory sticks and clean them with a pencil eraser. The technique here is to carefully rub the gold contacts (not across but down) each of the contacts to remove any oxidation that may have built up on the contacts themselves. Once completed, take a Q-Tip with rubbing alcohol and clean the contacts again. Before you put them back in, blow out the memory slots with canned air and make sure the alcohol has dried (use a clean dry Q-Tip). Then reinstall your memory sticks. Note: They will be keyed on the bottom and they only go in one way. Make sure they snap down tighly.

Next step is to do the same thing with your video card. Remove it and clean its contacts in a similar manner. Be particularly careful when handling your video card and touch the side of your power supply with your hand before you touch the video card itself. This applies whether you are taking it out or putting it back in. Once its clean, put it back in.

As an optional safeguard, you can unplug and replug each connector in your machine. This will help break any oxidized contacts ensuring a proper electrical connection. Do these one at a time and make sure they get securely reconnected. If you have any add-in cards (ie: ethernet, audio, modem, etc.) they too can be unplugged and replugged. Don't forget to ground yourself by touching the side of the power supply or something else metal before you go handling any components inside your machine.

Now you can plug your computer back in and test it. If you are still having problems we can be pretty confident that the power supply is on its way out. These things can be unpredictable. Quite often they go all at once and you can smell the ozone as they fry or hear them sizzle as the sparks fly but there are situations whereby they demonstrate an intermittent behavior similar to your machine. The easiest way to check this out is to replace the power supply with one that is similar and known to be good. Unlike our first few steps, this could cost you some money and depending on your level of experience or mechanical apptitude, you may need some help. Its not difficult to replace a power supply but some would be well advised to seek assistance from a more qualified friend or associate.

Let us know how this goes and holler back with any questions you may have.
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