When you open the Task Manager > Processes tab, two things to do;
1] Click on the CPU column either just once or twice. The object is to list the processes in 'reverse order', eg most usage at the bottom. That way you will see more easily the heaviest process usage as it happens.
2] If that Process tab has an option at the bottom of the page to "Show processes from all users", click that. Not all processes are shown until you select that. Then scroll down, if you have to, to see the bottom entries and look for any heavy usage processes.
Mark
Running vista on a Acer Aspire Timeline 3810T-354G25Mn notebook. Computer slows down to a crawl even with no applications running, task manager shows 100% usage, but none of the processes in TM show any significant CPU usage (< 3%). It seems some hidden script or process is doing something (is that possible without task manager seeing it?). I have to restart my computer to fix it, but it comes back eventually. Only app I really use is firefox much on it. Any ideas. Obviously could be a virus -though have Sophos installed from work.

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