Actually looking at my idle temps a bit more closely I'm not so worried about my Orthos readings. I'm idling at 33 at the moment at 3150MHz with my vCore at 1.4v, and during 3DMark runs it's only peaking in the mid-50s, so it seems that Orthos works the cores harder than any real world stuff. And it seems perfectly stable at these settings, gave me close to 12 hours of Orthos with no errors today. Pretty happy at 3150, I think I'll just leave it where it is for a while and enjoy it!
Midas, try setting your PCI-e clock back to 100- it really doesn't seem necessary to run it at 101 or 102 for me at least. And keep your Vtt down, just a notch or two above stock. I reckon 1.35-1.4 is fine for Vcore depending on clock speed, and the northbridge doesn''t seem to need more than 1.38 although it ndefinitely needs a bit of a boost.