Memtest errors for RAM over 2Gb

[skudzy]

Ive recently bought another two 1Gb RAM sticks to upgrade my RAM to 4Gb for Vista x64. After installing it the system was very unstable and kept crashing so i ran memtest. For any configuration which gave me more than 2Gb RAM, memtest throws up errors for most of the tests. 2Gb and below passes all tests and Ive tested each stick individually and they all pass. Any ideas what could be wrong? The tests implies its something to do with the setup of the system rather than faulty RAM.

Relevant Spec:
4x1Gb PC2-6400C4 Dual Channel Platinum Revision 2 XTC Series DDR2
Intel Core 2 Quad Pro Q6600 2.4GHz
Abit IP35-E PCI Express DDR2 motherboard

 

[skudzy]

I havent overclocked anything so that can't be the problem. I've tried memtest with 3 sticks in (3Gb) and it throws up errors for that as well. It only seems to like 2Gb or lower in the tests.

 

[skudzy]

Looks like i found the culprit. One of the new sticks fails every time it goes through memtest and won't boot the computer when put in on its own. Don't know how i missed it before. I guess that means returning it to overclockers.