Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

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've just built a new computer and it crashes occasionally - it just switches off and then restarts and I'm not sure about the best way to diagnose the problem. All the components are seated nicely and nothing seems to be overheating, the bios is set to fail-safe. What tools could I use to track down any possible issues?

I've run memtest86+ with no problems. It's running Win7 Ultimate.

share|improve this question

First thing to try is isolate between hardware and software problems.
Since you have already passed memtest, I'd suggest the following.

  1. Boot with a Ubuntu LiveCD and leave it up for a while (use it a bit if possible).
    If this crashes similarly, you have a hardware problem.
  2. If the problem reproduces in a very short time,
    Boot into the BIOS screen and leave it on for a while.
    If you get a crash here, again its a hardware problem.

If you rule out hardware problems, check your Windows7 drivers again.
Are they all correct and updated?

share|improve this answer
Ubuntu 9.10 freezes, although could be some sort of unrelated incompatibility. BIOS screen seems to be fine. I guess I'll probably need to start swapping out parts. – Alister Apr 8 '10 at 2:16
How new are your parts? Ubuntu 9.10 incompatibility that would lead to a freeze sounds unusual. And, how long did you leave the BIOS screen? at least 2-3 times longer than your mean failure time? – nik Apr 8 '10 at 2:18
All parts are new (Core i3 system with integrated video) I've had memtest going for quite some time without problems - which should be a bit more stressful than the BIOS screen. I'll keep trying various combinations. – Alister Apr 8 '10 at 3:07
Does the crash appear after a specific time? Is it always the same time? Maybe your Powersource doesn´t provide enough power for all of your Hardware. – Diskilla Apr 8 '10 at 6:49
@Alister: With Ubuntu freezing it sounds like your Windows is 'skipping' a bluescreen and is directly rebooting. Please try this to deactivate the automatic restart:… – Bobby Apr 8 '10 at 7:17
up vote 2 down vote accepted

After much testing, and trying a different motherboard (no joy) different CPU (still no joy), as well as memory, power supply, discrete video card - I did manage to get a configuration going by disabling Intel speedstep in the bios - and this now seems to be stable. One other thing that I did find out, was in the System Logs, the specific error was "Kernel Power" - if this helps anyone else.

Update: It turned out to be an incompatibility with the memory brand/type (the memory was not faulty however, it, um just didn't work in windows) - replaced it with some corsair memory and alls now good. Disabling SpeedStep improved the stability, but did not make it stable.

share|improve this answer

Which board and rams? If memtest passed then it shouldn't be a hardware issue. Flash it with new bios and see if it works this way.

share|improve this answer
Just a word of warning, I know it's rare, but still: If the flashing fails for any reason, you'll have a fancy new trivet and voided your warranty. – Bobby Apr 8 '10 at 7:19
I think it has the latest bios already. It's a gigabyte GA-H55M-S2H – Alister Apr 8 '10 at 22:31

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .