My PC started to stutter, the mouse pointer, typing, programs, all would repeatedly freeze every few seconds.
Task manager showed CPU usage, but not from any program, so I ran 'Process Explorer' which showed usage by 'Interupts'.
The problem turned out to be the IDE DVD Drive ! Disabled it from the 'Device Manager' and the stuttering stopped.
It may actually be the motherboard IDE at fault, so got a SATA DVD drive, which also gets rid of the chunky IDE cable 😀