CPU Usage

[Gunnar]

On my Win XP Pro system I can see that the CPU is
*always* used more than 50%. The odd thing is that the
Task Manager does not say what is going on.

The task list in Task manager is totally normal,
basically no process uses the CPU and the System Idle
Process is constantly around 96-99%

BUT looking at the bottom line of the Task manager (or
the system tray ikon) reviels that the CPU is in fact
used 50-65% constantly! Judging by the CPU temperature,
this is actually true (i.e. the 50-65% CPU usage).

I've tried to stop all processes and all services as far
as possible. No change in CPU usage. Reboot doesn't help.
All the latest service packs and hot fixes is installed.

How can I find out what is using my CPU? and why dowsn't
Task manager show it?

 

[Gunnar]

It's wierd, isn't it?
I have updated virus protection with real time scanning.
Added to that, I now and then scan my system for
spyware/trojans etc, so I'm confident that my system is
clean.

 

[Alex Nichol]

On my Win XP Pro system I can see that the CPU is
*always* used more than 50%. The odd thing is that the
Task Manager does not say what is going on.

The task list in Task manager is totally normal,
basically no process uses the CPU and the System Idle
Process is constantly around 96-99%

BUT looking at the bottom line of the Task manager (or
the system tray ikon) reviels that the CPU is in fact
used 50-65% constantly! Judging by the CPU temperature,
this is actually true (i.e. the 50-65% CPU usage).

I would speculate that you have some check around (eg by a firewall or
AV) that is tapping in to the idle loop, in such a way that the two
metrics are giving different results - one including it in 'idle
process' and discounting it and the other not