Something's strangling my cpu

[hut49]

My pc has suddenly become almost unusable with cpu usage spikes of 80% plus occuring every 60-90secs. These surges of CPU activity last about 10-20 secs. The problem is so bad the mouse locks up until the CPU usage drops!

I've looked at running processes and the ones that are consuming cpu during these spikes are taskmgr / svchost (several) / explorer.

I've run (in safe mode) AdawareSE, spybot and Antivir (all updated versions) and cleaned anything found - but no virus detected. I ran scandisk - ok - and defrag - not needed - and I've used Registry Mechanic (found over 800 problems (!) but despite fixing all of these the underlying problem remains.

I used Hijackthis to create a log. Where's a good place to post this? Anyone got any ideas what's the problem?

Thanks

Nick

[coach]

I had this, followed same process as you and found nothing.

PC died once on a hot day after about 3 months of this which gave me a clue..

Loaded up the motherboard & PC diagnostic monitor in window and noticed the temps were within 2 degrees or so of the BIOS danger temps

Cleaned everything out inside including the processor heat sink which was VERY clogged with dust and had no airflow

All cleaned out - no slow going at all now!

Coach

[Plotloss]

You are seeing a spike for TaskMgr because you are using that to view the processes, there is a cost and thats what you are seeing.

Explorer is the shell containing the start bar etc, every time you launch an app you will see a spike here and then that use is palmed off onto the launced process.

Svchost is tricky because its a process that is used to glue a load of other processes together so its difficult to discover what that particular svchost instance is being used for.

What happened immediately before you started noticing this useage?

[hut49]

Thanks for the suggestions.

I've been trying to isolate the cause and found that when the pc's not connected to the internet everythings fine - cpu usage running about 2-3% flat line. So I don't think an overheating processor is the cause.

When I enable the netgear wireless connection the problem starts again, 70-80% spikes that take about 15 secs to subside then repeated regularly every 50 secs or so, with the 'baseline' cpu usage wobbling around 4-5%.

I thought the first evidence of a problem was the mouse becoming jerky and slow to react (isn't that a PITA) but guess this was just a symptom of lack of cpu capacity. I changed the mouse just in case (uninstalled software and then reinstalled) but no difference.

So should a wireless card be performing like this? Maybe I should try uninstalling and reinstalling? What do you think?

[Munter]

How many copys of explorer are showing up in task manager? I had a similar problem with some dodgy program called explorer that wasn't the explorer from windows!

[rsvmilly]

If it wasn't internet dependent I would have said defrag and free up some space.

I reckon it sounds like you have a trojan.

I had a mail-relay trojan on mine which Norton completely failed to find. As soon as I put AVG on, it found it immediately.

[jeremyc]

Are you seeing internet traffic at times of high CPU load?

It might be worth disabling all access via your firewall then selectively enabling again until you find the culprit.

You are running a firewall, aren't you?

[rolex]

Plenty of info here and you can post your hijack log
www.short-media.com/index.php

>> Edited by rolex on Tuesday 27th September 16:28

>> Edited by rolex on Tuesday 27th September 16:29

[rebelstar]

Try using ProcessExplorer from www.systinternals.com - it's better than the standard task manager because when you see a peak in the graph, you can move your mouse over it and it will tell you which process was busiest at that time. It's got loads of other nice features too, of course

[hut49]

Thanks for the continuing suggestions.

Jeremy - yes I do have a firewall and I did what you suggested. Interesting to see the list of 'exceptions' that had built up over time and I got a great sense of satisfaction in clicking the 'restore default' button. But alas no improvement!

I used the site you suggested Rolex and trawled through some very interesting stuff. Eventually it looked from some of the problems I reviewed on that site that it could be a wireless software and XP service pack 2 interaction.

The wireless card I had was Netgear WG311T with driver version 3.0.0.43 and sure enough on the Netgear site was a 3.2 version download. It mentioned specifically that it was designed to fix the Windows problem!

It did exactly what it said on the tin! The difference in computer performance is simply unbelievable. Now the PC is pretty silent whereas before the hard disk was constantly active when I was connected to the internet. I didn't for one minute think that installing some updated software for the wireless card could make such a difference.

I now have all my CPU resources back and no spikes on the task manager performance chart.

Thanks for all your help - that sysinternals.com site has some very cool freeware - just right for those upcoming winter evenings when the Tiv is tucked away!

>> Edited by hut49 on Tuesday 27th September 19:03

[rebelstar]

hut49 said:

just right for those upcoming winter evenings when the Tiv is tucked away!

Judging by your profile pic, the Tiv stays out to play in the winter! Bravo!

[hut49]

rebelstar said:

hut49 said: just right for those upcoming winter evenings when the Tiv is tucked away! Judging by your profile pic, the Tiv stays out to play in the winter! Bravo!

OK - it's a fair cop! I'm not just a fairweather tivster!