In reply to a post by ian72:

Sorry to reply to me but thought easier than editing.

Having checked the OS you are using something seems really strange. Have checked 2 different versions of win7 and neither of them show the system idle at process at all

That's handy to know - I've learned something there

In reply to a post by ian72:

I am wondering if it is some sort of malware that is hiding itself under that name (as that is how XP would have shown free proc).

That sounds like a promising theory.

The message came via the control panel. It seemed OK. Im going to run the programs you suggested. I wasn't suspicious as everything is brand new, computer, internet connection etc. I expected that amount of updates.

Windows 7 does show System Idle Process, but only when you select "Show processes from all users". Makes sense as the "process" doesn't belong to the logged-on user.

You can't kill the System Idle Process (obviously, as it's not a process); there is no right-click menu at all for that item.

Could just be that the system is re-indexing everything as there have been substantial changes. That fits with your description. Worth running a malware scan anyway, but I don't think you have anything to worry about. It will settle down soon.

Might be swapfile thrashing the drive. What's your reported percentage used memory (very bottom of task manager in performance tab)?

Surely it wouldn't take over 3 hours?

Its changing from 60% to 70% and everything inbetween.

Which processes are using the processor time whilst it is peaking? Just watch Task Manager and check (make sure that you watch processes from all users). It should then be fairly simple to check which is the culprit.

Virus scanning is another possibility; that can take a long time when there have been significant changes.

I think you nearly have it mate!!! The system idle process is peaking when the CPU usage goes to 100%. That should be impossible. Im in the middle of running a virus scan. It has recommended that I delete some cookies but surely this isn't the cause?

It has nothing to do with cookies. You can delete those.

Any clues here?

http://www.computing.net/answers/windows-nt/system-i...