Pentium D 2,8 ghz socket lga 775 malfunction?

[idata]

ok ,pentium D socket 775 processor dualcore 2,8ghz ,checked with intel processor id,checks out allright 2 cores functioning.

but...on my motherboard asus p5rdv-1 ,running win 7 only one core is active????

taskmanager shows only one core,even bios shows only one core.

only way to let the bios show 2 cores is when i activate hyperthreading...but this processor doesnt support hyperthreading and windows will not boot when its on.

ive been searching for a solution for days now and i dont know anymore.

Any related cases here?

Any solutions/answers?

Help

[idata]

try a ubuntu linux on cd-boot and run program administrator-->system monitor

if all core works, it's a problem of win-7 reinstall or modify flags or variables with regedit

[idata]

ok tried that didnt work,and my knowledge of the register is limited.

it does however show up in sisisoft sandra benchmarkingtool,verry weird.

still it doesnt show up in the bios,only when i set hyperthreading to on it will show 2 cores,but since this processor doesnt support HT ,windows will crash on startup.

Any other ideas anyone?