Gary,what do you mean by 'it is running smoother' even though fps are unchanged?for example i have the problem that even with 30+fps i get little stutters no matter which scenery i am overflying. this is most obvious during turns. i get 2 or so stutters per second i would say. they are little, but they are there.i have tried the most famous tweaks (fsx.cfg changes, newest direct x and nvidia drivers) but those didn't help. i have a 7800GT.did those mini-stutters disappear after changing to dual core? is that what you refer to?thanks to all of you that replied.regards

Ironic that you ask this question right now, as I am currently fighting stutters trying to love FSX again in a flight from YSSY to PHNL in the LDS 767. Even throwing two cores at it, I am getting major stutters when panning the view, even over clear ocean without a cloud in sight! For me, it takes an hour or two before the stutters appear, so my comment above was moreso relating to short duration flights. But for any long leg flying, FSX turns into a stutter mess!Sorry, but dual core is only doubling my frustrations at this time ;-)Gary