smb@research.att.com (Steve Bellovin) writes:
> I'm getting sig11s running gcc.  I know that that generally indicates
> memory problems; what I'm at a loss to explain is how that can be
> happening.
> 
> The machine in question is a Thinkpad T21.  I have two 256M SODIMMs.
> Either alone works fine.  With both in, I get sig11s.

This is exactly what one would expect to see if the capacitive loading
of the drams causes the memory-bus timing to be pushed over the edge.

With the current tight memory timing margins this is such a problem
that many current Intel-brand motherboards will automatically turn off
aggressive timings if they sense that a large number of DRAM chips are
present.  (Eg. they'll downgrade 2-2-2 timing to 3-X-X).  If your BIOS
give you control over the dram timing, crank it down a bit and see if
the machine stabilizes.

Also if the memory is aftermarket and not spec-ed to work with
computer, if could just be on the hairy edge.  Loosening the timing
should help here too.

-wolfgang
-- 
Wolfgang S. Rupprecht 		     http://www.wsrcc.com/wolfgang/

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