ACPI Warning, then hang

[Bryce Edwards]

I'm getting the following warning, and then the system locks:

ACPI Warning: Incorrect checksum in table [(bunch of spaces)] - 0x29,
should be 0x48

Here's a pic: http://db.tt/O6dxONzI

System is on a SuperMicro C7X58 motherboard that I just upgraded to
BIOS 2.0a, which I would like to stay on if possible.  I tried
adjusting all the ACPI related BIOS settings without success.

Bryce