Can't figure out if it's my memory... Hammer Test crashing?

[maxiedaniels]

After Apple inspected my 2013 Mac Pro for what seemed to be the graphics card crapping out (artifacts and UI lag), they came back and said my memory failed a test. I had put in OWC memory, so I called OWC up and asked for an exchange. I installed the new set and tried MemTest Beta 3, because I was curious about the hammer test. I started a full test, including the hammer test - my computer crashed when it started the hammer test. I've retried this multiple times, it always crashes on the hammer test.

If I don't use the hammer test, my computer will show no errors and not crash for ~24 hours (the longest test I've done).

Is this just an issue with the hammer test itself? Or is my memory bad again? I'm curious cause my computer still has graphical errors and I suspect it may actually be the graphics card.

[keith]

It is possible that performing the hammer test caused bit flip errors in memory used by the UEFI BIOS subsytem, causing it to crash. Does the crash occur immediately or after the test starts running for a while.

If you have the log file please upload it or e-mail it to us.

The hammer test exercises an extreme case of memory access that is highly unlikely to occur during normal operation, so it is not unusual to see errors (see this paper for more details). If your graphics problem still occurs after switching out the RAM and you're not doing anything unusual with the memory (eg. overclocking), it is more likely that it is something else.