Fruityrudy

Hi guys , I just bought me a new pc and it runs like a train but not when i play Arma 2. Its a intel i7 860 quad core 2.8 , 4 gig ddr3 ram , Ati 5850 1024 video card. When i play the game all the graphics are fine and clear but i have massive annoying stuttering on all resolutions and settings. I tryd different graphic drivers and even reinstalled arma 2 without patch 1.5 and after installed again with the patch. Can u guys plz help me out ??? im desperate .....