Some quick research shows that my VCORE is one setting too low (XPC7451RX800RE should be 1.64, mine is at 1.59). However, in the example in the linked article, the VCORE is intentionally set lower than suggested due to heat issues. Would such a small discrepancy cause such problems as I have?
Freescale lists a specific VCORE in their documentation, and says that the voltage should be within 50 mV. 1.59 should be within that limit still, but at the lower limit.
We encountered may stability issues with incorrectly set VCORE in the past, so I would suggest to raise the VCORE to the correct value, but make absolutely sure that you have adequate cooling...
Edit: Also, make sure that you clock it at 800 MHz. It's a genuine 800 MHz CPU, but I've heard of a lot of people that clocked theirs at 933 MHz ...
