I might miss mentioning a step or switch the order of events because I did not take notes.
I was using a DZ68BC (BIOS=0028), i5-2500k, 8GB Crucial Ballistix Tactical DDR3-1333, and Seasonic 650W PSU which has been running for about a year in its present configuration. I powered it off to change SSDs -- I'm playing with Linux distributions -- and when I powered it back on, I noticed that the time was off by hours (it might have been that way before). Okay, so it needed a new battery. I just happened to have a new CR 2032. So I powered it back off and replaced the battery. I powered it back up, changed the time in BIOS, and installed Zorin OS using a CD-ROM I have used a few times already. It finished normally and told me to remove the disc and reboot. That's when things changed.
I removed the disc and pressed Enter as instructed, but instead of rebooting the PC went to a screen I had never seen on this DZ68BC, but I have seen it on my DH67BL, the screen that indicates that it is trying to perform a network boot. That's strange, because I disabled network boot in BIOS, something I always do. Okay, I'd start fresh. I rebooted, entered BIOS, and pressed F9 to return to default, but after saving the system returned to the network boot screen, which kind of made sense because that was now enabled. I rebooted and pressed F10 to select the booting device because I thought everything was normal. However, in the list of bootable devices there were three entries: the CD-ROM drive, the Intel 530 SSD, and IBA GE Slot 00c8 v1365. Oh boy, that's not good.
So I powered down and pulled every add-on card out of the case -- Creative sound card, SIIG USB 2.0, and SIIG USB 3.0 -- because that message looked like the PC wanted to boot from a PCI or PCIe slot. I powered up and immediately after the BIOS screen saw the message Machine Check Error. Oh boy, big trouble. I rebooted again and saw the same message. I powered down, removed the battery, and let it sit for a five minutes. I put the old battery back in, hit the power switch, and saw the blue light flicker just for a second and the fans started turning, but then it shut down. I tried it again with the same results. I switched back to the new battery, but same results.
It looks like either the processor or the board is toast. I just happen to have a spare DH67CL board and a spare Sandy Bridge processor to try both components, but I'd like to hear the official explanation of Machine Check Error and IBA GE Slot 00c8 v1365. I understand there is no warranty. I will update this post as I learn more.
UPDATE: It's the board. I bread-boarded the DH67CL with the same memory sticks and i5-2500k and it booted right up into BIOS. Oh well, the DH67CL always worked okay. Scott will be ecstatic to know that the DH67CL BIOS was updated into Sandy / Ivy territory from before.