Undocking Panels FPS/Vsync problem

Hi,

After a long time customer with AMD (HD5870,HD7970GHZ Edition) i just moved to the Nvidia Camp (GTX780SC,EVGA) and i can tell this was the right choice in terms of performance .Smoothness is also totally a different storie (for the better) DX9 is like DX10 with AMD

I plugged in the new card hoping not to reinstall my hole system again and found everything to work great besides when in DX10 undocking panels.

When i do this the FPS jumps in a pattern from for instance 45fps to 30fps(spooling up and down- not in a instant move) and reset itself again after 20-25 seconds. This scenarie keeps repeating ifself making the flight a bit stutter not much because the GTX780 seems to be a beast but sometimes 30 fps IS better than 17 :-).

There is no issue in DX9 btw.

I have tried with different drivers from 327.23-331.65-331.82 with same results. With and without Steves DX10 fixer.

..

So... :-)  i did a total re-install of my W7-64bit and FSX and this time ensuring Windows do all the updates before installing FSX.

I installed FSX in this order on a seperate drive :

FSX

SP1

SP2

SDK

SDK1A

SDK2

But i still have this issue so either i am doing something wrong in the process or something else is going on.

I have no virus scanner and i have deactivated Windows Defender ,Firewall and Diskdefragmentation. 

I did not have this issue with AMD so i am a little lost. Hopefully you can guide me in a direction to look at ?

Thanks in advance

(PS i have also a post in DX10 discussion and on Geforce, Nvidia forum)

fsx.cfg . I have tried the ForceWindowedVsync=1 but that does not help with this :-)