Why does "system" use 100% CPU

[John Perry]

Using Windows 2000 with all patches.

My machine has gone really slow, and I can see from Task Manager that
the "system" process is using all free CPU cycles to maintain CPU usage
at 100%, so doing anything is very slow. Reboots temporarily fix, but
does anyone have any idea on how to fix properly? No other programs or
processes are using more than normal CPU%.

Thanks

 

[Stubby]

You've got something else going on. The System Process is what runs
when there is nothing else to run. It has rock bottom priority so it
won't compete with anything you want to run.

Maybe your paging file is too small. Or maybe you just don't have
enough RAM. Or something could just be swapping lots of pages to the
hard disk. Or you are snapping stuff across a network.

Maybe you have some malware that is choking your system. Run Ad-Aware
and SpyBot.

 

[Roberto Ruiz]

Stubby, check on Processes in Task Manager which is the process grabbing
the CPU cycles, if you find it you might do something about it. If explorer
is the process stealing the processor time, you may solve the situation
temporarily by closing it and launching it again from task manager instead
of rebooting, but in this case, you probably have a virus o adware running
as a subprocess, so you would have to clean it by using proper
anti-virus/anti-adware or reinstalling the system. Sometimes I have seen
this problem caused by defective video codecs.

Hope this helps,
Robert
Roberto Ruiz
Brainbench MVP for Win2000 Professional
http://www.brainbench.com

 

[John Perry]

Does this make sense. I have an Athlon 2200MHz which I run normally
with a system clock of 133MHz and with memory at the same speed using
CL3. But, when I reduce the system clock to 100MHz and the memory to
the same 100MHz, and effectively under clock to 1500MHz, the problem
goes away. I am using 2 x 512MB Crucial memory, so I'm hoping it isn't
the memory that is at fault. Case runs at 31C and CPU at 42C, and the
HDD is 37C. Machine sits behind a router with Norton AV and Adaware and
also Spybot, and no problems seem to be there.

I now wonder if I have a memory problem. How did I find this? Well
machine rebooted and reset BIOS to standard default setting, and I
forgot to reset the clock speeds.

Very strange.