Processes dying with signal 11

[Wojciech Puchar]

>>> The problem I see is that after a few hours of running buildworld,
>>> when it starts building clang itself, 'as' crashes with a signal 11.
>>>
>> always at the same point or in random places?
>>
>> if first - it's probably not hardware problem.
>
> It's at a random location, but it always happens after the build has
> been running for a few hours and when it's ended up swapping some
> processes out of main memory.  I've read

so it is hardware problem.

As it start crashing when swap is used, it may be not memory but chipset 
problem - works fine until disk I/O is used.