[SOLVED] 100% CPU after Clean Install !

Brad

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Hi Guys,

Hoping someone can help me out here ..

Just done a clean install of Windows XP on an Acer Aspire 1640Z

Once installed and logged in, noticed it was a little "laggy" upon opening the task manager I see the CPU is at 100%??

Also the touchpad is not responding very well .. not moving when using the touch pad and jumping all over the place.

I left it for a few days and came back to it, to my surprise its fine ? So it got me thinking was there even a problem in the first place ? I install the drivers, updates etc all fine.

I leave it for a while and turn it back on to finish it off, but then the problem is back ? 100% CPU again and totally unusable.

It is perfect in safe mode though? And it cant be virus / malware related as its a clean install ?

Part of me if thinking thermal problems / damage .. but then why would it be fine in safe mode ?

I am just installing windows 7 on it, in the hope this cures the problem. Very confused, I have never seen this problem again ? To note, it responded fine during the XP install, and right now during installing 7 it appears fine...

Hope someone out there could shed any light on it?

Cheers.
 
From memory, the only services using high CPU, where System and System Idle Process ...

I don't remember svchost using a high amount but will check out next time.

Cheers.
 
I wouldn't have through spending a fortune on a windows 7 licence in an effort to see if the program goes away is a good idea.

I would assume he is just doing it as a test and has not actually used a license on it yet. Or is there something against using the 30 day trial without intent to purchase in the EULA?

I would either be thinking a bad update snuck in, or maybe some driver problem, or hardware. And I would say it could still be hardware even if it acts fine in safe mode. I think the windows 7 test is a good idea. Have you already done HDD and ram tests?
 
I would assume he is just doing it as a test and has not actually used a license on it yet. Or is there something against using the 30 day trial without intent to purchase in the EULA?

I would either be thinking a bad update snuck in, or maybe some driver problem, or hardware. And I would say it could still be hardware even if it acts fine in safe mode. I think the windows 7 test is a good idea. Have you already done HDD and ram tests?

Yeh I have just put 7 on it as a test as a trial ...

So clean install of 7 and CPU Usage is sitting at 95-100% usage ..

The top processes are:

System
System Idle Process
svchost
svchost

Even whilst the CPU is so high the touch pad is a little more responsive .. If i put in a USB Mouse it moves fine, you wouldnt even think there was a problem ! This just gets stranger..

Haven't done a test on the hardware as of yet ..

Cheers.
 
Did you install windows 7 on a different HDD, or the same one? I'd start by swapping the ram, then start disconnecting everything you can.
 
System Idle Process shows the system is idle. If it's high, then the CPU is not being used for that percentage.
Try Process Explorer and Process Monitor to see what exactly is using the CPU behind the scenes. Hover over the svchost processes to see exact details and take it from there.
 
This is what I get from task manager after a fresh install and just logged in ...

351y53r.jpg
 
I'd use Process Explorer to narrow down that 50% System resource.

In the mean time, my gut feeling is the Windows Update module.

You haven't given us a lot to go on (in my opinion).
What install media? (Acer, OEM?)
What service pack?
What updates have you run?
Have you defragged it since the install?
My own experience with Windows, is 35% fragmentation after most installs. Sometimes upto 50% after updates.

Andy
 
Pull out the battery. Then report back.

Not a totally random suggestion, as I had an Acer in once which pretty much the same high CPU usage and taking out the battery 'cured' it. I investigated it some at the time and it seems that there is a bug in a certain energy management driver which polls the battery (to check it's charge state) but somehow with a bad battery ends up using near 100% CPU cycles. Seems that Microsoft has been carrying this same bug for a very long time (although apparently they tried to fix it), so I assume it only kicks in with some strange combination of factors.

My 'fix' was to disable the device in devmgmt but only because the machine was almost going to the dump.

EDIT: who uses Taskman? Gives you next to nothing even in Win7/8. If you want to trace what something to servicehost or hardware interrupts, you have to use process explorer.
 
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I'll try to run process explorer to find out exactly whats using it.

Its an Acer Aspir 1640Z

Installed with Windows XP Home SP3

No other updates since fresh install...

Haven't tried a defrag yet..

Cheers.
 
Pull out the battery. Then report back.

Not a totally random suggestion, as I had an Acer in once which pretty much the same high CPU usage and taking out the battery 'cured' it. I investigated it some at the time and it seems that there is a bug in a certain energy management driver which polls the battery (to check it's charge state) but somehow with a bad battery ends up using near 100% CPU cycles. Seems that Microsoft has been carrying this same bug for a very long time (although apparently they tried to fix it), so I assume it only kicks in with some strange combination of factors.

My 'fix' was to disable the device in devmgmt but only because the machine was almost going to the dump.

EDIT: who uses Taskman? Gives you next to nothing even in Win7/8. If you want to trace what something to servicehost or hardware interrupts, you have to use process explorer.

Thanks for that suggestion, I will give that a go, funny you should say that the battery looks like it is bad anyway .. so that may well be my problem !

Thanks.
 
I'll try to run process explorer to find out exactly whats using it.

Its an Acer Aspir 1640Z

Installed with Windows XP Home SP3

No other updates since fresh install...

Haven't tried a defrag yet..

Cheers.

As you haven't done any updates to the install, then I would definitely do this. Do *all* of the updates, not just the standard automatic ones. There was an update earlier this year that addressed the 100% CPU utilization, and it was due to Windows Update.

Defrag will not resolve the issue, but I would definitely do it once all the updates are applied.

Andy
 
Thanks, I will try to do the updates also and see if this resolves the problem.

Thanks for the help all.

Cheers.
 
KompuKare - Thanks ! It does appear to be the battery to blame !

I booted up without the battery in and it has been very responsive and low CPU ...

Put in the battery and it ground to a halt with high CPU ... ejected and fine again. I have never seen a faulty battery cause that type of problem. Will definitely be remembering that one !

Right now I am just re installing a fresh XP on it so that it hasnt been touched, that will then be the true test.

Thanks again !

Brad.
 
KompuKare - Thanks ! It does appear to be the battery to blame !

I booted up without the battery in and it has been very responsive and low CPU ...

Put in the battery and it ground to a halt with high CPU ... ejected and fine again. I have never seen a faulty battery cause that type of problem. Will definitely be remembering that one !

Right now I am just re installing a fresh XP on it so that it hasnt been touched, that will then be the true test.

Thanks again !

Brad.

Well it's not the battery as such. More like the power management driver polling like mad in an endless loop. AFAIR, it is an actual Microsoft supplied one too. You should be able to bypass it by disabling the relevant driver in device manager though.
 
Well it's not the battery as such. More like the power management driver polling like mad in an endless loop. AFAIR, it is an actual Microsoft supplied one too. You should be able to bypass it by disabling the relevant driver in device manager though.

Yeh good point, I will check that out once the reinstall is complete.

I guess yeh it must be constantly polling and due to the battery being faulty it not get an "answer" and so just eating up all the CPU ?

Cheers.
 
Yeh definitely that at fault.

If I disable the ACPI Battery driver it kicks in straight away !

Cheers.
 
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