It was definitely memory. My money says that the original power supply was still good. The memory all passed mem check, but it has run for the last 48 hours with three sticks. Getting ready to cycle the remaining three through to see which is toast. It won't run with all six.
I didn't lose anything since there was nothing wrong with the hard drive that was removed -- plus I use offsite backup for everything...
I may poke around and see about upgrading the ram.