Re: Crysis low, med, high, very high screen compare here
I never had any problems with Vista and I'm looking forward to play it in DX10. I do think some of the "bonus" DX10 effects will probably make it to DX9 through .cfg file tweaks but I do expect them to have a lower performance inpact in DX10.
The engine is clearly aimed towards the future hardware, enabling for instance 4096x4096 soft shadow maps will bring even a GTX to its knees (beta2 - low teens to single digit fps at 1080p) and the raytracing/light reflection effects (that are still in the engine, r_sun something command) are possibly too taxing as well.
Intel I7-920 aircooled by Prolimatech Megahalems @ 3.8Ghz (200x19) | Gigabyte GA-X58-UD3R | OCZ Platinum 3x2GB DDR3-1600 RAM (7-7-7-24) @ 1600 | Gainward GTX 480 | WD Raptor 74GB + 150GB + Samsung 1TB | Soundblaster X-Fi Platinum | Corsair AX850 Gold | Coolermaster Stacker 830 silver | Logitech Z-5500 Digital 5.1 | Logitech G15 keyboard | Logitech G25 Racing Wheel | Sharp LC-46 XL1E (gaming and work)