mcelog memory errors

Allo all

I keep getting the same error on a box in mcelog.
It is intermittent so it takes long to troubleshoot.
It is an intel board with dual quadcore processors with hyperthreading turned on.
I have taken it back to the vendor and after testing it said the ram is fine, memtest also confirms this.

I am suspecting the memory controller, but need to document my proof.
Yet this suggests it could be a mcelog problem

Anybody out there have the same issue?

HARDWARE ERROR. This is NOT a software problem!
Please contact your hardware vendor
CPU 0 BANK 8 MISC 400010881 ADDR 6aa49600
MCG status:
MCi status:
MCi_MISC register valid
MCi_ADDR register valid
Transaction: Memory read error
Channel: unspecified
STATUS 8c0000400001009f MCGSTATUS 0