Guys, FINALLY after a month, i "found" a solution. I don't even have to overclock my CPU, stock is enough. This http://isiforums.net/f/showthread.php/5260-Read-this-if-you-have-in-game-stuttering did the trick Damn "Microsoft Visual C++ 2010 redistributable" should be rfactor2 Number 1 enemy. EDIT: forget it, it was lucky day, troubles came back after.
After 2 months, i finally got my old copy of XP, and installed it in another HDD. That made the trick, game runs fine now, without micro-stutters or FPS drops. Its just xp sp3, WITHOUT any other programs, just for rf2, CPU does not go to 100% anyomore. So for you guys, if you have any performance issues, try reinstalling windows. I took so long to try this, because every other game runs fine om W7, but rfactor 2 doesn't. Some windows issue, other programs, i have no idea, was taking resources from rfactor 2.
My view on this is that if every other game runs fine on win7 then it's an rfactor2 issue. I can't afford to have an rfactor dedicated machine/os. Hopefully the ISI guys can sort this out.
You would think that would be correct Elbo, but unfortunately there is always a possibility that rF2 uses things that no other game uses, which might have issues in Windows already. If this is the case, then rF2 would highlight problems with Windows where other games would not.
