I have recently built a new system and I`m having a problem with unusually high cpu usage. From a fresh install of windows xp, Task manager is reporting cpu usage of 0% at idle but when I install my graphics driver the cpu usage is 65 - 90% the whole time. Any suggestions on why it might be doing this and can anything be done to reduce it?

In task Manager, under the processes Tab, look at what application is using the CPU intensive. It's nice to be important but it's more important to be nice...

Thanks for your reply, system idle process is showing a constant 90 - 100 in task manager

System Idle process is just that, a measure of the IDLE capacity of the CPU. I doubt it shows as 100 but would fluctuate up to 99. That is normal. Check this against the CPU Usage in the performance tab of taskmanager. When System Idle is at 99% the CPU Usage should be showing either 0 or 1% If your CPU Usage is consistently showing high then there has to be some process running that is using it, and it won't be System Idle. I used to have a signature but it disappeared and I just couldn't be bothered writing another so please feel free to ingore this.

system idle is showing 99 every other process is around 00 yet the cpu usage is still 60 - 80% the whole time, the strange thing is it only happens when the graphics card drivers are installed, before that the cpu usage is down to 0% - 5% when idle

I'd be searching for a different/updated or older graphics driver. I used to have a signature but it disappeared and I just couldn't be bothered writing another so please feel free to ingore this.

where are you seeing that the cpu usage is 60-80% ??