It's like talking to a wall.
The MOBO does matter, because some MOBOS has limits, cheaper ones in particular.
The power consumption can be doubled, because if you really OC to the max you have to tweak with the voltage which will increase GPU temperature which will further increase and the power consumption with it. I've done it myself.
You can never get full physx on a CPU.
Great that AMD has some AA, but it does not matter, because I talk about FXAA and TXAA.
Hilo1222, just go with whatever you feel like, there are pros and cons with both GPUs. Go read some reviews and comparisons, because this has no ending, we both seem to have a colored opinion about the two brands. Both Cards are great deals, but if ou wanna go AMD then wait to Q1 of 2013, AMD will be launching the 8000 series.