Overclocking a laptop isn't a fanzy thing if the cooling system is good, in my case Asus done things right as the result this laptop probably has the best cooling system ever made.
I've overclocked my core GPU from 775Mhz to 910Mhz and it still remain under 67°C MAX
Besides, the fan remains silent
In fact, my cooling system and GPU overclock isn't the actual problem ...
The only think I didn't know is that we couldn't overclock a Sandy Bridge CPU other than 2500k and 2600K.
And I wouldn't do such things if SE optimise it for multicore cpu and I'm surprise that some fans make some soft to do it ... I know that SE is busy right now but I don't understand why this is so badly optimized with new hardware like mine (i7-2670 is not a poor old cpu right ?).
My question is what settings / hardware do you have to play it in 3D without lag ?
ABout the 2.0 Engine I wonder if it will needs even more power than this one ?