AMD K8 memory bug with more than 2 banks

Eric W. Biederman ebiederman at
Thu Mar 18 21:57:01 CET 2004

"Hendricks David W." <dwh at> writes:

> I have applied your fix and booted it up on a Tyan S2885 mainboard with 
> four banks full, but have not noticed any change in non-reserved 
> registers on the AMD 8111. Can you please elaborate on exactly what 
> changes I might observe? I want to check out the specifications on the 
> memory we're using and make sure we're getting the right values.

The fix is correct.    And it was a good catch.  My apologies
for the delay in communicating.

That line is one half of a read/modify write cycle and all it does
is to clear the old value out of the register.  The per
DIMM value is 4 bits long, which is the reason for multiplying by 4.

The index values will be 0,1,2,3....


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