Just took a look at the results from 12+ hours of logging yesterday after pulling chainminer v1.2. The board looks quite stable and error rates dropped significantly (~1% over the entire peroid). I'm looking at 36 GH/s sustained over long periods just dc fans and no heat sinks. I've manually clocked all chips at 54 and have not noted any benefit in using the auto feature in v1.2. Now someone push the board up to 40 
how are you making that sort of log? Im moving to manual tuning now, since most chips are stable at 54/55 with 1% errors and 36Ghash/37Ghash-nonce.
if it runs well for the next few hours i will consider moving the resistance from 1.178 to 1.165 (before it gave me issues, but that was prior to chainminer update)