Quad core server freezes often

Hey there...
For some time, i've had a server running, and after i've changed tower on it, it has started to crash like a mofo.
so...
I've tryed a lot of things to try and help out the problem, at first I thought it might have been the PSU, got a new one, still didn't work.
Ran some diagnostics through Hirens Boot cd.
The first couple of ram tests went alright, but when I did a stress test it went cold at 94 %...... :(
- Also tryed switching around my 6 GB of ram, even took most of them out at one point..
Now here is my question.
Am I the only one who thinks the next thing to change is the MB?
Or is there some testing sofware I need to know of?
Would be nice to have some sort of log that I could post, but since the computer freezes, it's like it never has the time to do a log..

Looking forward to your reply.
 
Is your motherboard touching anything in the back or is there a cable touching your motherboard?
 
Sry for the late response..
It's been running without crashing for the past few days.
Untill today..
No wires are touching the MB.
Again it looks like it's every time I "stress" the computer it crashes..
So think I'm just gonna get a hold of a new MB... :(
Never had this situation before.
 
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