Something like every second hour I run my computer, my CPU suddenly only has something like 10% of capacity. This is not because of some process taking the rest of the capacity, it is the CPU itself that is suddenly running slower. After this has happened I can for example try scrolling a webpage in Firefox, just to see that the process is taking up almost 100% of CPU (seen in Task Manager), and the scrolling repaints something like every half-a-second.
The only way I have found to fix this, is to restart the computer and it will once again run on full speed.
It seems like this happens more often if I have been running programs, which require lots of CPU processing, so it might be related to heat.
Is there any way to diagnose the problem.
EDIT A diagnosis dump from CPU-Z after the slow state has occured can be found here.