Treacan wrote:

Seti is slowing my computer using 98% of CPU. As soon as I quit Boinc
the CPU usage goes down to 2%
Windows XP 2GHz 500 Ram

It is normal/wanted/OK.
Seti runs at a lower priority than the other processes. If no processes are running on the cpu, seti will get the cpu for nearly 100%.
But if now a process with a higher priority requests CPU, the scheduler (from the OS) reduces the CPU from the seti process, and give it the process with the higher priority. This reducing is so fast, that you don't feel anything.

Lars