I just installed a few days ago this board on my system and the NB and SB have very high temps idle 55-56/C load 58-59/C maybe 60/C; the asus claims that the board can go up to 90/C . But high temp will overheat the rest of the components and all of them will have a higher temp. The voltages are set to manual from bios so there is nothing set to auto that the board can change.
First i will change the thermal paste.
Then i will check if the coolers flat side it is full flat.
Change integrally all MB coolers.
Use water cooling.
If you have other sugestion please help, if you have the same MB please post the temps.
My board hit 39 degrees (4ghz OC Q6600) and stays like that. Asus packs an extra NB cooler so maybe try installing that? Personally don't worry those temps aren't very high anyway. Try sorting out the air cooling in your case.