Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a problem with one computer.

  1. It restarts very frequently after some time of being powered up, even being idle sometimes.

  2. Moreover, (only in some occasions) when i push the power button it doesn't do anything (it remains shutted down)...To fix this problem i must wait some hours and then it starts working "magically" or i must disconnect the power supply cable from the motherboard and connect it again.

  3. Finally, the well known blue screens of death randomly appears. They aren't the same, they are different.

These are the three symptoms. I have done some things to try to fix this problem but i cannot achieve that. The things i have done are the following:

  1. I have tried changing the power supply. I have connected 2 others power supplies and the problem persisted.

  2. I have cleaned the memories and connect them to other RAM slot, but the problem continues.

  3. I have checked the CPU temperature with SPEED FAN and it showed that the temperature was 51ºC (Is this a high temperature for CPU?). I have cleaned the dust from the CPU but the problem persists...

I'm not at home now and i don't remember the exact models of each component, i will edit this post as soon as I arrive home with the correct specification of my computer.

CPU: Intel Pentium 4 2.6 Mhz


RAM: 256 RAM 333 mhz

HD: 80Gb WD

Power Supply: 500 watts

I have discard SO problems, hard-disk problems or memory problems because of symptom number 2 That's very strange, is like something in the mother or in the boot process.

Thanks and hope you could help me.

share|improve this question

I would have said change the PSU, but as you have already said that, I will skip that step.

Take a look at Bluescreenview, this utility should allow you to view any previous blue screens. Try to see in more detail if there is any links between the problems.

That being said, due to the age of your computer (a P4 with 333mhz memory), it is very likely that your motherboard was probably one of the many millions affected by faulty capacitors, or it has simply had a good run and reached the end of its life.

Blown capacitors -

Blown capacitors can be the cause of many "random" problems which appear to be completely unrelated, very annoying and hard to diagnose.

alt text

The top should be almost flat (with slight indents out embossed sections depending on specification... look at the middle one) but you do not want to see any big bumps such as the first one or any leakage as the last one.

share|improve this answer

From what you tell, my first guess is the system gets too hot. Thats not just the CPU, but any part like the RAM, the power converter, stuff like that. When it crashes, run your fingers over the hardware and touch all parts. If anything is so hot you remove your fingers instantly, it is too hot. Maybe use one of those touch-free thermometers. Also, the part with the photo of Elkos is a good idea. Asrock used a lot of cheap components.

Do a system check. First and easy is memtest86+. Download the current release, burn and boot the CD. If the computer runs more than an hour with that, start looking for other stuff. Try having the computer run 48hrs on memtest in the end.

Boot from a Live-Linux CD. Does that run stable? If yes, grab another hard disk. We´re on superuser here, you have a couple of disks lying around, havent you? Make a fresh install. Make a test after each installation step.

Download the "ultimate boot cd" and fiddle with what it has to offer.

share|improve this answer
memtest would be the best way to isolate memory related errors. +1 – Sathya Nov 9 '09 at 17:59

51C is not especially hot for a CPU, but do you know the temp of your GPU (the processor on your video card)?

share|improve this answer
This should have been a comment, not an answer? – BinaryMisfit Nov 10 '09 at 9:17
Maybe it's an incomplete answer. The suggestion was that the OP check the temperature of the GPU. – CarlF Nov 10 '09 at 18:39

I've had a similar problem in the past with my P4. What fixed it for me was replacing the "goo" that sits between the CPU and the heat sink. In my experience, the CPU never got all that hot, but the temperature would spike and cause a shutdown. The goo that came with the CPU had essentially dried out over the years and was no longer making much of a connection. It had a vaguely voodoo feeling to it, but I picked up a $10 tube of the pretty good stuff at Fry's, reattached the heat sink and the the problem went away.

share|improve this answer

Things to worry about...

  • bad motherboard. PC's are made with cheap electrolytic capacitors that have short lifetimes that additionally vary with temperature. One bad cap won't do any harm but if a bunch of them go bad they need replacing or just a new system board. There are better (solid tantalum) capacitors but they are a lot more expensive so they are never seen in peecees

  • high power (hot) IC's don't actually last forever despite their lack of moving parts. Manufacturing defects or things like metal migration can cause chips to go bad. Solution: replace system board or CPU.

  • overtemperature CPU crash. It's rare to see thermal grease used on a mass-produced machine but a machine built by an individual or shop may well have used it. Thermal grease does a good job for a while but is known to not age well. Thermal interface pads are a better alternative. Do not take the CPU heatsink off unless you are prepared to replace the thermal interface with either thermal grease or a new pad. The pads are not reusable. I have heard of people using nothing at all and producing spectacularly unreliable systems.

  • overclocking. Try underclocking.

share|improve this answer

If it is rebooting without a BSOD or other error being displayed, you could investigate the Windows Crash Recovery settings which may give more clues. I had nVidia driver issues once which were causing exactly these sort of random reboots.

Right click on my computer > Properties > Select the 'Advanced' tab > and under 'startup and recovery' click the 'settings' button. This will open a new window, and under the 'System Failure' heading, uncheck 'Automatically restart.'

share|improve this answer

I had this happen to me just this weekend. It turned out to be my video card. The card was not overheating or anything apparent. I swapped out the card for an old one I still had and all the issues stopped.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.