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

Possible Duplicate:
What is the proper way of debugging a slow Windows installation?

I've been running Windows 7 on my laptop for about a year now, and have had no issues regarding speed. About a month ago, my computer had what I refer to now as an "episode" where it runs extremely slow, when I open Task Manager I see no significant processes running, nothing out of the ordinary, but my computer is at 100% CPU usage.

Usually restarting fixed this problem, but it seems to have gotten worse to the point where restarting does not fix this problem, and it's interfering with my work.

What should I do?

share|improve this question

migrated from Jun 7 '12 at 3:56

This question came from our site for professional and enthusiast programmers.

marked as duplicate by Oliver Salzburg, Nifle, Ƭᴇcʜιᴇ007, Shinrai, Mokubai Jun 7 '12 at 21:56

This question was marked as an exact duplicate of an existing question.

How's your hard drive functioning? – Blender Jun 7 '12 at 3:59
@Glen654, click the Show Processes From All Users option in ask Manager to see system processes. My bet is that one of the instances of svchost is the culprit, in which case you’ll need to use ProcExp to figure out which service is the problem. – Synetech Jun 7 '12 at 4:05
Run a good anti-virus and/or anti-malware program. – Mike Dunlavey Jun 7 '12 at 5:52

There are many factors that can cause a computer to a halt. It could be a overheating processor, a failing component such as the hard drive, a runaway process of some kind hogging memory or the processor or even a malware infection.

A good tool that can be used to check for both overheating processors or failing hard drive is Speedfan as it can show cpu temperatures and hard drive SMART status. If your CPU is overheating then you may need to open it up and clean the dust out of the ventilation holes. If the hard drive is reporting excessive failures or errors then it may be that it is failing and needs to be replaced.

For malware checking I would recommend Malwarebytes Antimalware.

share|improve this answer
Very unlikely that the cause of his symptoms has anything to do with the CPU overheating (though of course the CPU will get hot while running 100%). – Daniel R Hicks Jun 7 '12 at 11:35
CPU overheating can cause the processor to throttle back in order to cool down, though granted I would not expect it to be as severe as the OP seems to be stating. I have a couple of work colleagues who've made a quick bit of cash by buying a "strangely slow" laptop on ebay only to clean out the dust and thus restore it to full performance then (after verifying that it was "fixed") put it back on ebay. This was usually P4 based machines iirc. – Mokubai Jun 7 '12 at 11:39
But if CPU overheating were the problem you'd see the processes in Task Manager chewing up lots of %. That's not the case. My bet is on a wild interrupt. – Daniel R Hicks Jun 7 '12 at 16:47

On Windows 7 there's a great utility called "Resource Monitor", it will show what apps are using the disk/cpu/network/memory (sort by the different columns to zero in on a particular resource usage).

Fire it up and watch what's running. Also, have a look in your Event Viewer to see if there are any services having a problem during start-up.

share|improve this answer

There are 2 questions noted in the wiki. Both should be sufficient starting points:

share|improve this answer

See here. There are things such as the interrupt mechanism that can peg the CPU without showing up as processes. ProcessExplorer (available free from MS) is helpful.

share|improve this answer