4 hours ago, vortex681 said:

When you changed graphics cards, did you fully uninstall the NVIDIA graphics drivers and reboot the system BEFORE installing the new card? If not, try a full uninstall using Display Driver Uninstaller from https://www.guru3d.com/files-details/display-driver-uninstaller-download.html followed by a fresh install of the new driver using the "clean install" option as shown here: https://support.ubi.com/en-gb/faqs/000025720/Nvidia-Driver-Clean-Installation/

..that is exactly what I did uninstalled with DDU & clean install of the latest driver  which worked well with the 970  

save the file first make a copy, right-click-drag-drop the file , menu appears, choose copy.

C:\Users\YOU\AppData\Roaming\Microsoft\FSX\fsx.cfg

in there will be some sections something like:

[DISPLAY.Device.NVIDIA GeForce GTX 980.0]

delete the line [..] and the following lines under that section, do not venture into other sections [..]

repeat for all similar sections.

save

run fsx and you will have to go to setting and choose your screensize.

..so this is the current situation Frame locked via application. & I get 29-30FPS graphic quality is great, no stuttering no shimmering etc, all clear and smooth though I noticed that when flying some of the objects (like the huge gas tanks next to LAX are pupping ups and despairing but no big deal 

Open a new Cockpit view dropping it of in the small 15" and booomm, Frams drop to 14-16 ...... the graphic is still great, but I was under the impression that with my spec I'll be able to hook 3 monitors with no issues, and with what I see it will be impossible to add under monitor needles to say migrating to P3D v4  .... to be honest I'm very upset & after all the investments I mad on my Rig I feel hopeless    (:-

Tnx you guys for all your help & support

Undocked view halving the fps. Can you try another driver version?

I can get similar with undocked if the sim is not the foreground app. But I've seen similar low fps with undocked views cured by choosing the NVidia Control Panel Restore Apply on the profile. If the profile is greyed out change something so the restore appears then apply. Seems odd thing to do but there's more going on under the hood after that.

..okay. Picked up some interesting things

First lets forget about the Full Screen and Wind mode, this is not the issue.

As mentioned the issue is reduction in FPS /Performance when opening a new window in secondary monitor. No matter what I did opening a new window "Slice" FPS almost to half.

So yesterday I tried a different approach, I started a flight at San Jose in NoCal outside FTX SoCal coverage, and ,wahlla, no performance degrading, all smooth at 30FPS, so eventually, we should put the blame on ORBX, however, the interesting thing is, when I entered SoCal FTX it kept the 30FPS ...very weird ... 

I'll keep experimenting and report