Alan Cox wrote:
quoted text
> On Wed, 3 Oct 2007 22:35:24 +0300
> "Pekka Enberg" <penberg@cs.helsinki.fi> wrote:
> 
>> Hi Linus,
>>
>> On 10/3/07, Linus Torvalds <torvalds@linux-foundation.org> wrote:
>>> I would bet that the reason the intel-optimized memcpy triggers this is
>>> that the non-temporal stores just means that you go out directly on the
>>> bus, and it probably just shows a weakness in the chipset or bus that
>>> doesn't show with the normal cacheline accesses.
>> But that should show up with memtest too, no?
> 
> Not neccessarily. The old VIA memory copying bug only showed up with
> prefetching and mmx store patterns. That was a hardware flaw that took
> extreme memory utilisation to show up - so it does occur but thats not to
> say it is the cause
> 
> Alan
> 
This is way out of my depth, but I have re-seated my 2x256MB DDR single sided DIMMS and checked my BIOS, though the Phoenix BIOS in 
my rebadged CLEVO D400E doesn't allow any tampering with timings, and recompiled with the USERCOPY enabled but still get the bit 
corruption.
Since I seem to be alone in getting this effect perhaps my machine is dodgy? I've attached my dmesg output if that's of any help.

Neil.