In message <59cc77be050314201332cda391@mail.gmail.com>, David Shaw writes:
>It was even cooler... I suppose that rules out overheating as an issue?
>

It would seem to.

Have you checked your BIOS configuration for speed, wait cycles, etc?  
Are you sure your memory is the right speed for your motherboard?  (I'm 
grasping at straws here...)  Have you tried running one SIMM at a time? 
I once had a laptop where either card alone tested fine, but but 
together generated random failures.  The cause was apparently 
capacitance right on the edge of the spec.  I eventually ended up 
ordering two new DIMMs from a single vendor; that worked.

		--Prof. Steven M. Bellovin, http://www.cs.columbia.edu/~smb