Sorry I haven't been reading through all 10 pages of replies, but:
COUGAR: What do you mean by "works perfect" ?
I have AMD X2 5200+ and the difference is barely noticeable. Few FPS up, yes, but I'd hesitate calling it "perfect".
Which is by no means meant in the bad way, it's just that we have all been warned XP users won't see much difference. OS problem or something.
COUGAR, please state what is "perfect" for you. As I sure as hell wish it would be perfect for me too. :)
The most difference I've seen so far is by turning cockpit detail to 256. Great boost, 10-15 FPS! Love it!
UPDATE:
I'm terribly sorry, my fault, haven't detected the new DCSMax 1.4, will try it today after work.