Crap... I forgot to mention I did some preliminary tests:
Memtest86: Overnight, both sticks in Channel A, 3 (or was it 4) passes
Prime95: I actually downclocked my memory back to 1333 and it ran for the whole day while I was at work on Blend.
BIOS already on latest F9 for my board, and already went beyond the listed drivers
from Gigabyte (11.6 for Intel RST, 17.3 for LAN).
I might try running Prime95 on 1600 tomorrow while I'm at work. Right now I upped the Vcc as well. Thing about this 124 is that it is extremely infrequent, like once a day or two, at very random times, so it's not really consistent on what I'm doing when it happens.