Just thought i would let you know my experience of updating my system from XP DX9 to WIN7 DX10. It has made a huge difference for me. In XP DX9 i had to have most video settings at low and the game crashed at least once every 2 missions. In Win7 DX10 i haven't had a crash yet and can get 40+ fps over land and 70+ over water with most settings at medium and some at high. The game also just looks and feels that much better. As you can see below my system is quite old now so i am amazed at how well the game plays.
Specs:
core 2 duo (6400) @ 2.13GHz (o'clocked to 3.3GHz)
GTX 275 (o'clocked to 830Mhz)
4GB Ram
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