So my 3 ASUS ROG MARS cards with 2 GTX 760 chips on one PCB arrived.
I am currently having some thermal issues with the cards not receiving enough air. Some of the fans run 100% and the GPUs still show 98 deg C.
And this is with Yacoin which doesn't max out the TDP fully

Christian
Sorry pal, but i´m not surprised!
I´ve got:
1x GTX 660Ti with standard (reference) cooler
1x r9 280x with one of those dual-fan ""coolers""

(like the ones those asus rog mars have)
both of them installed in my normal computer case.
It never had any trouble with temperatures with just my nvidia card.
But when I installed my r9 280x, suddenly BOTH cards were running way too hot, my 280x didn´t even use its full clock.
I noticed that the reference cooler managed to get tons of hot air out of my case, however my other card was just "feeding" all its heat into my nvidia card.
Personally, i solved this by buying a watercooler for the 280X

Now i can overclock my 660Ti by about 30% (1215Mhz)! without getting really bad temps.
(yes the one with the standard nvidia cooler!)
Of course I could oc my 280X really good now but since cgminer is stupid, i haven´t tried that.
Conclusion: NEVER buy a video card with those stupid two-fan coolers!
They may be a bit more quiet if it´s your only card in the system, but as soon as you have a second card, you´re gonna hate them.