Expert: Keith Davis - 9/7/2008

Question
Hi there my sons PC constantly reboots . It gets up to where  it gives me options on how i would like to restart my computer in safe mode with the most recent settings or start windows normally. i have tried ALL the options but  the screen to load windows comes up and then the comp restarts this cycles endlessly. Sometimes I do get to use it but then it goes into the reboot cycle again.  Not sure what to do.  After being on a while, it does make a loud humming sound from the tower.  Maybe this has something to do with it?  Hope you can help me fix it.  I am good with following step by step directions.  Thanks!

Answer
Jennifer,

The humming noise makes me first think it is one of two fans. Either the processor fan or the power supply fan. Second, it could be a hard drive going bad. We'll go through this step by step. Of course if you get to one of the steps and find a problem there is no need to do the rest of the steps.

1. Check the processor fan. The only way to check this fan is to take the side cover off and turn the tower onto it's right side (right side when you are facing the front of the tower). When you do this you will see a small fan which is pointing straight up. With the computer on it should be on at all times. Turn on the computer until it reboots and see if this is where the noise is coming from or if the fan is turning. If the fan is not turning at all the processor is overheating and the computer will reboot on it's own.

2. Check the power supply fan. You will be able to see the power supply fan by looking at the back of the tower. It will be the fan closest to where the power cord plugs in. Same thing here; when the PC is running the fan should be running at all times. When the noise starts see if it is coming from the power supply.

3. Hard drive- With the side panel open, when the noise starts, if it is a bad hard drive the noise should be coming from the front of the machine near where you turn it on.

4. Make sure the noise is not coming from the CD/DVD drive by putting a disk in and see if it makes the sound when spinning up.

Let me know what you find out with these troubleshooting steps and I can advise you on where to buy a new part if needed.

Keith