Paul NZ :
Is BIOS 1006 or higher on it now?? Thats the BIOS it needs to support that CPU
I think you need the correct BIOS to even boot into the BIOS.
If using all six cores cause crashing, I'd suspect:
1) bad CPU core
2) overheating issue
3) Motherboard voltage not stable under load
We need more info:
Was CPU working before?
Are you overclocking?
Did you check temperatures for each core?
Sometimes the thermal paste isn't done properly and leaves a gap. In general, I just use the 5mm pea method. Put in center and place cooler on top. Some use thermal pads which shouldn't be an issue.
I've never seen a CPU work like that though, so my TOP CHOICE is a bad CPU.