>FYI, there is a chipset from Intel that supports ECC.  Some motherboards
>that use it also have the support.  I think it's called "Triton-II" on the
>streets.

In fact the machine with the memory problem _does_ have a Triton-II
chipset. Or at least, that's how Linux reports it.  NetBSD doesn't
recognize the PCI-bridge part of the chipset, even with PCIVERBOSE.
NetBSD 1.2-beta from 1996-08-01 says:

vendor 0x8086 product 0x122d (class bridge, subclass host, revision 0x01) at pci0 dev 0 function 0 not configured
vendor 0x8086 product 0x122e (class bridge, subclass ISA, revision 0x02) at pci0 dev 7 function 0 not configured

I don't know if the mboard I have supports ECC. If it did, surely it
should inform sw of correctable errors.  I didn't notice anything in
NetBSD that supports such notification on x86 machines....  then
again, I'm a relative neophyte here. Is there support for this that
I'm overlooking?