Goodly morning all...

This is taking awhile...

FSX and Windows 7
REX2
ORBX
Frame Rates set to 30...during flight frame rates stayed in that area...
Video Driver is up to-date for the GEForce 580 and is Driver Number 296.10
Stephane here are a couple of things that were different than yours on the NVIDIA Inspector and yes I checked both areas...

FEATURE SETTING
Ambient Occlusion OFF
OPTIONS
OFF Performance Quality
Antialiasing Setting 16Q CSAA
OPTIONS
-Application Controlled
-2X
-4X
-8X CSAA
-8
-16X CSAA
-16XQ CSAA..........this is the one I am using
Antialiasing OFF...have a look at the aircraft antenna...

Antialiasing ON for remainder of shots....

See the difference in the aircraft antenna from the 1st shot...





Comments and advice most welcome...