Problems with >16GB RAM in P6T SE

System runs OK with 4 x KVR1066DN3N7/4G (on the compatibility list for the mb) installed but when I add the final pair performance slows dramatically and CPU usage increases significantly (to the point where even small tasks require 98% CPU usage and the system is practically unusable).

I have tried swapping around bays / slots / chips with same success / failure results. Also tried with 2 x 2GB chips in final 2 slots - same result. But with all slots filled with 2GB 1.6v Corsair 1600 chips everything works fine.

Tried clean boot - no conflict identified, didn't fix problem. Tried increasing DRAM bus voltage to 1.58 - made no difference. Is there a tested bios setting for 6 x KVR1066DN3N7/4G with my processor/MB that is known to work? My PSU is 1000w - so there should be enough power.

Spec:

*Product Model : P6T SE
*Motherboard BIOS Revision : 0808 (set to defaults - which according to Kingston should work)
*CPU Type : I7 920
*CPU Speed : 2.67
*Memory Vendor : KINGSTON
*Memory Model : KVR1066D3N7/4G (all tested with memtest - zero faults)
*Memory Used : 24GB (X6)
*Operating System : Windows 7 64bit

Any suggestions or even theories greatly appreciated.

Cheers,

David

Have you tried down clocking your memory to a rated speed like 1066 or 1333. I have heard some people having problems with overclocking the memory when all six slots are filled.

Well I'm glad you solved the problem. I hope I don't run into any problems with my asus motherboard after hearing about their crappy customer service. Maybe when I was trying to decide between the Asrock x58 and the asus p6t v2, I should of gone with the Asrock