I recently assembled a new computer

Asus P4G800-E
P4 3.2 HT (130nm)
Dual 2x512Mb RAM
SATA RAID 2x200MB
GeForce 6800 Ultra GS
Audigy2 ZS Platinum Pro
Windows XP Pro

All is fine, however Seti@Home is running at 50% CPU when the machine is 
idle, and it NEVER goes above 50%.

Checking the devices it appears Windows XP claims I have two P4-3.2 
installed, and right-clicking on a process lets me set the affinity and 
choose which processor the processes are allowed to use (CPU 0 and/or 
CPU 1).  But I only have 1 (one) !!! CPU.

So, now Seti runs at 50% and Idle processes run at 50% which I suspect 
means that Seti is only running at half capacity.  If I maximize (show 
graphics) Seti goes to 99% cpu, but switches back to 50% when I close 
the window.

Anyone know what to do?
I tried to manually delete both processors from the device manager, 
but after a reboot they are both back.

Morten