In article , "R. C. White" wrote:
Hi, Tanix.

Had something similar after upgrading ram from 2 to 4gb. Memtest ran
fine...

I ran memetest86 for at least 20 hrs. No problems.

Like Wes, I had problems after doubling RAM from 2 GB to 4 GB last year.
I've never run FireFox at all. When Vista went RTM 3 years ago, I rebuilt
my computer to celebrate. I got a new mobo/CPU/RAM all from NewEgg a kind
of a matched set: EPoX MF570sli mobo/AMD Athlon 65 X2 5000 CPU/2x1 GB OCZ
PC-6400 SDRAM. This ran Vista Ultimate x64 just fine for about a year.
Then I ordered another 2x1 GB OCZ RAM from NewEgg, identical to the first
pair. Everything was good for about 6 months.

Then random BSODs started happening. I tried MANY fixes, starting with a
through internal cleaning, new Antec PSU, even a new 1 TB SATA HDD.
Memtest86 said all the RAM was fine. Finally I gave up and took it to a
reliable local shop that I've dealt with before. Casey tested it thoroughly
and replaced 3 fans, but the problems quickly returned, so I took it back to
the shop. He ran some more stringent RAM stress tests and said that it
passed them all, but when he took out one of the two new sticks, the BSODs
stopped. I ran for the next few months without that one DIMM and had no
problems.

When I contacted OCZ for RMA, the tech insisted that I send BOTH new sticks
so that they could be tested by the factory as a matched pair. OCZ sent me
2 new DIMMs; again, apparently identical to the original pair. That was
last Spring and I've had no more BSODs. ;)

My point is that some RAM problems are so subtle that we really can't
diagnose them in the field. And the problems they create can mimic almost
any kind of computer defect, sending us on many wild goose chases. The one
consistency is inconsistency; we seldom get the same Stop Code twice. We
can suspect the PSU, the hard drive, drivers, applications, heat buildup,
RFI...just about anything.

You might want to contact the maker of your RAM about a warranty replacement
of some or all of your memory. Many brands sell with a lifetime warranty.

RC

Yep, there are things like DMA transfers, burst mode and you name it
related to ram. I bet the memtest86 is way too primitive to exhaustively
test all the access modes. Just flipping bits around can only detect
the obvious cases, such as some data bits being shorted out and things
like that. But ram was the first thing i suspected. We'll see how it goes.

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