?!

I've got a 7900GTX, P4D @ ~ 3.9, 2G DDR2 and on high it runs with 20 FPS and looks so freakin amazing. On medium it's smooth and looks ok too. Worser than FarCry? You should test if you graphics card is broken

Edit: I'm sure the game is so slow because of your cpu, or in the words of my friend "3200er schimmelt doch schon". The AI and physics need much power.