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CPU running at 100% but nothing running! HELP!

I have a Celeron 2.5GHz, 760mb RAM running XP SP2. Now and again, my computer just grinds to a hault. Things still work, but very, very slowly. When I open task manager the performance tab reads CPU running at 100%, but when I click on Processes (and with all users checked) it read 00 in CPU column for ALL programs. Apparently nothing is running, yet the CPU is at full hilt. The only way to stop it is either wait it out and (most times) it eventually sorts itself out and returns to normal functioning or Restart. It is very annoying and shouldn't really happen.

Help, please help.

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Since it's a single core...

In reply to: CPU running at 100% but nothing running! HELP!

Windows can go 100% CPU bound in some driver or service and not show up. In fact my favorite one are network shares that are offline and every 10 minutes the CPU gets busy.

Your post tells so little that maybe you can share more. If it is truly hidden tell us what you do to look for ROOTKITS which hide quite well.


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What else do you need to know...

In reply to: Since it's a single core...

What else can I tell you that you need to know... I'll do anything to stop it doing this. What's this ROOTKITS thing you talk of? Is that a program that I can download that searches for things that are hidden. By the way my issue is a regular one, it only happens once in a session, not every ten minutes... And if something was running in the background, would everything else really read 00. It says nothing is running despite that I could have MSN, IE7, AV, firewall all running....??

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There's a clue.

In reply to: What else do you need to know...

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In reply to: There's a clue.

I'm running Sygate Personal Firewall.

As for turning some programs off, makes no difference. Whatever is running, they all read 00 in the CPU column on task manager despite also saying the CPU is at 100%. It seems to happen just after startup. I wondered if it was due to IE7.. any thoughts? I'm running RootkitRevealer now.

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I don't run IE (any version.)

In reply to: more....

Sorry. Can't comment on that...


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You're infected

In reply to: more....

You are infected with either spyware or a virus. First turn off Systme restore. Rt clcik My Computer/Properties/System Restore Tab.

Then open Start/Run/ and type msconfig. go to the startup Tab and uncheck everything. will be prompted to so.

Get these programs and run them in safemode. All are free
AVG-anti virus
Spybot Search and Destroy
Spyware Blaster
Google for them you will find them all.

This should fix it. Keep them all up to date and run often.

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no i'm not

In reply to: You're infected

did all that, i'm not totally stupid. besides, why would it only work for some of the time and then resolve itself and only do it on some start ups - viruses are always going...

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Don't be so sure...

In reply to: no i'm not

I've found some nasties that elude the names of antivirus. Mostly those rootkit varieties. Share more clues for us to work with.

If we reach a dead end, a post of your HIJACKTHIS and EVEREST log output files could give us a peek under the hood but reading such is optional here.


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Ok so you think you're not infected

In reply to: no i'm not

Go to the the task manager. Open the Processes. Start ending processes one at a time and see if CPU usage drops. You may have a program running with a memory leak thus the CPU usage is eaten up.

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