I'm no expert at this. In fact, this is really the first time I've really attempted mining. I had tried it before on my MBPro before just to get familiar with the whole process but didn't bother beyond that...
Tonight I'm running my brand new MP2013 8core 32GB w/Dual 700's. After fiddling a bit with the "Intensity" setting, here's what I'm getting:
Both GPU's @ Intensity Auto: hash rate = varies from 55-211kH/s, GPU Die Temps 78 C, Fan rpm = 800-900
Both GPU's @ Intensity 12: hash rate = 1.27MH/s, GPU Die Temps 79-84 C, Fan rpm=1540
Both GPU's @ Intensity 13: hash rate = 1.72MH/s, GPU Die Temps 84-86 C, Fan rpm=1550
Both GPU's @ Intensity 14: hash rate = 1.75MH/s, GPU Die Temps 86-88 C, Fan rpm=1615
Seems like intensity 12 is cruising speed, 13 is about max, 14 just pushes temps higher without much increase in hash rate.
Are those numbers any good?
When the Mac Pro fans hit 1900, it makes a pleasing whooshing sound. It's not harsh or loud, kind of sounds like the ocean from distance.