Computer freezes running parallel vasp (and sometimes serial too)

[cat54]

I am running VASP on Ubuntu using a dual quad core processer. When running parallel, depending on how big the system size is (e.g. 12 atoms) the computer completely freezes up giving no error messages anywhere. Also if I run serial VASP, but run a few programmes at once, it also crashes.

Some observations I have made:
12 atom systems will crash on 4 or more(out of total of processers
96 atom system will crash on 3 or more processers

With all runs the memory capacity is no where near reached, and the computer can easily crash when using less than 10% of the memory.
There are no soft limits on the version of Linux I am using either, only hard limits

The point at which it crashes can vary i.e. can be before the first iteration has started, or can be at the 40th iteration, and if I run exactly the same programme twice, each time it can crash at different iterations too

I know this may not be a problem to do with the actual VASP programme itself, I think it may be to do with the bus or stack, but I am not quite sure what and need some advice on what it may be.

Any help at all would be greatly appreciated, thankyou

[alex]

Sounds very much like a faulty memory. Please check you memory with a proper tool.

Hth,

alex