I RMA'd the RAM. Should be here on Monday.
Meanwhile, people on the UbuntuForums are continually adding to my thread with personal experiences with weird issues with systems they built. Someone posted this picture:
So, this begged the obvious question - what were my error code lights?
On the right where PH1, PH2, PH3 are - they're all solidly lit up.
LED 1 - Flashing on/off in a steady fashion.
LED 2 - OFF
I see that LED 1 - ON/LED 2 - OFF = memory error. But my LED 1 is flashing. Would the LED's on the right side (PH1, PH2, PH3) being all solid and lit up be an indicator that I am getting proper power to the board? Is this indication of a memory error?