> >On Thu, Oct 07, 1999 at 10:09:23AM -0700, Matthew Dillon wrote:
> >> Intel's ECC implementation is not perfect (1), but it's good enough to
> >> catch these sorts of problems.
> >Just as an interesting side note, we had a motherboard which
> >supported ECC ram and had ECC ram in it and which was crashing.
> >Eventually we discovered that every 8th byte in page aligned 4KB
> >chunks was becomming corrupted.
> >We replaced the ram and saw no improvement, and then got a replacement
> >motherboard. As far as I could see the only significant difference
> >between the new and old motherboard was the addition of a heat sink
> >to the memory controler chip. The machine is now perfectly happy.
> >So it seems that ECC isn't enough if your memory controler is too
> ECC doesn't protect against certain types of motherboard address line
> errors (since although the ECC is correct, the selected address is wrong, so
> thus the data is wrong). There's parity protection on parts of the CPU
> address bus, but I don't believe there is any protection between the memory
> controller and the DIMMs for this type of problem. A handful of metal
> filings is also known to cause problems when it is dispersed properly. :-)
Your suppose to remove the motherboard before drilling holes in your
chassis!!! :-). And be careful when you strip them there screws out,
that little bit of metal filings is enough to through one for some
real loops. A good blast of 60psi dry air does wonders for ``fixing''
some of these really strange problems :-)
Now if I could just find something that would get sheet rock sanding
dust out of tape drive mechanisms, a dunk in the freon tank often
works, but that also cleans out all the lubrication :-).
Rod Grimes - KD7CAX - (RWG25) firstname.lastname@example.org
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