For some reason my chip doesn't seem to respond really well to cold.
I haven't gotten it extreme but I shivered though amibients of 16c and water temps down to 19c and it only gave me an extra 50Mhz.

Core temps didn't really seem to be a problem (45c under extended load).
The chip just doesn't seem to like voltages over 1.475....

I does pretty well though at ambients, and on water I got an extra 25mhz on the core and almost 300 on the IMC.
I'm pretty happy with the results but I can't seem to get 30 minutes Prime at 4.1, and taking the voltage over 1.5 causes more problems than it fixes. Guess it's not cold enough....

Here's what I'm using 24/7 stable with ambient water.
Not too shabby!