After 1 year of heavy usage it really has serious heating problem (mine was going up to 90°C according to SpeedFan)...
I didn't manage to find a way to change the internal fan speed...I tried a lot of programs, but nothing useful..
I solved opening it, removing the dust with an air compressor and adding 2 cooler master fans below (
this one) + one of those side air pulling fans (it gave me around -3°C).
Now I get to play without any problems to AC III blackflag, FarCry 3 and other heavy stuff reaching maximum 60-70°C.
I still didn't try to change the thermal compound (it's really a pain to reach it), but I bet it would decrease even more the heating.