In guru3d and techpowerup, in gaming loads, they pull more or similar amounts gtx 480. Maybe only by 20 watts at times, but that still more. Thus to make an educated guess that 290x consumes as much as fermi is pretty safe to assume.
In addition they both operate at 95 degree and at that point, 290x still continue to throttle in test by HARDOCP. Hardocp had to set the fans beyond the uber limits to stop it from throttling and where it can maintain 1000mhz.
At this point, they actually beat Titan significantly(10% maybe), but noise goes up beyond fermi levels, beyond dual cards.
So it is very much a fermi, but Nvidia had a better excuse for it. That being, it was generation one silicon and it was even bigger than 290x is. AMD has lots of experience with 28nm and they are designing a refinement of GCN rather than a whole new architecture like fermi.
The amount of heat it can generate is spectacular.
http://hardforum.com/showpost.php?p=...10&postcount=2
An overclocked a 290x can get even in the 80's C with water cooling, I have never seen a card do that.
Add in the overvolt overclock studying with techpowerup and 290x is indeed piping hot.
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