I7 920 Only Shows One Core



I have an ASUS P6T Board
Intel 920
750 Watt PSU
2x750GB HHD in Raid0

I built this computer roughly 6 months ago. And was using Windows 7 Beta Build 7100. And it worked fine there are 8 cores and my system rating was 7.7 or 7.5.
I upgrade to Windows 7 64bit 7600 after it came out and it worked fine. I installed a CPU moniter gadget and it worked fine for about a week. That when the bars changed colours and didn't look right anymore. I open Task manger and i see only one core. I updated the system rating, and it went down to 5.5. The system has slowed down alot now. CPUID also shows 1 core.

I tried MSConfig
and Reseting most of the bios settings ( all but changed IDE to RAID)
I have also tried re-installing Windows 7 and Windows Vista. No difference. Asus tells me its Intels fault and Intel reverses it back to Asus. What should I do?
I am going to update the bios but I dont think it will make a differecelogix_2006@hotmail.com