A couple other questions. After some conversations here, it was suggested that the memtest86+ program overrides the ECC checking. So that if the BIOS has ECC enabled and memtest86+ is run with the default settings of ECC mode disabled, the memory will not be tested as ECC memory. Likewise, if ECC mode is disabled in the BIOS, but enabled in memtest86+ then the memory will be tested as ECC despite the BIOS setting. If this is all true then I guess I may have a bad chip of parity memory. My understanding was that the ECC memory DIMMs had a extra chip for the parity memory so this could go bad yet the memory itself could still be good. Jack