Go into control panel, hardware device manager click on the cpu.
It should show 2 if hyperthreading is working.

It isn't, this's the matter. No way to see 2 CPU's and everything is
ENABLED to do it. I just have to identify the problem among :
P4P800 DeLuxe, P4 2.6c, WinXP PRO ...

Any ideas?

Fabio