So you are going throug the CPU Host/BUS to Oc, then depending on the setting you use that determines the DRAM freq, and is prob why at 1558 or the 779 x 2.
Yep , I just went ahead and upped the CPU bus to 240 so the ram is running at 1600 and ever so slightly upped the vcore voltage. As far as i can see right now even with the cpu multiplyer left at 17.5 and the cpu clocked now at 4.2 its looking stable. 40 mins into prime 95 and using the browser to type this my temps have not exceeded 52 celcius.
Id be almost willing to wager this chip could handle a little more even with some more fine tuneage of the voltage. I haven't tried to go lower at all with it, I started in reverse from stock until I came down to these temp readings and didn't attempt to go any further down until the pc would no longer boot windows like some had suggested.