Uhhuh. NMI received for unknown reason

[William Murray]

  Hi guys,
         I just today got a couple of errors like this on a Dell D610:

BillMurray kernel: Uhhuh. NMI received for unknown reason b0 on CPU 0.
BillMurray kernel: You probably have a hardware problem with your RAM
chips
BillMurray kernel: Dazed and confused, but trying to continue

  I tried running RAM self-tests, but they report all is fine.
Should I worry?

  About 2 weeks ago I closed the laptop with no user logged in,
forgetting suspend-to-ram would not work. An hour later I took it out
of my bag, very hot. Very. It was all funny - but after a reboot seemed
OK, but I suspect it has been taking longer to boot/login. Hard to
be sure, and this was 2 weeks ago, the error started today.

   Any thoughts anyone?
      Thanks,
            Bill