Okay, here is the flight report.

Standard ~2 hour flight KMIA-KATL from cold and dark to shutdown t gates

FSX is run in windowed mode with care added to ensure it does not touch menu bar.

Frame rates are set to UNLIMITED.

Test aircraft is the 727 (yes Im aware of what forum this is, but the problems I have with 757 is pretty much similar.)


In general windowed performance is pretty awful.
Roughly 10-15 FPS LESS than fullscreen.

To be honest about halfway through the flight I give up on windowed and switch back to normal.  

During the two hour flight I found it necessary to save and restart FSX 3 times, each time able to resume from saved spot.


Detailed below:

START FSX

Start up Procedures

Exterior FPS~70-80
VC FPS~20-25

TAXI to RUNWAY

Exterior FPS ~30-40
VC FPS~ 5-14


SAVE AND RESTART #1

Continue taxi and climbout from Miami

Exterior FPS~ 50-70
VC FPS~ 20-35

LEVEL OFF

Exterior FPS ~40-50
VC FPS ~15-20

20 Minutes into Cruise
Exterior FPS~15
VC FPS~7-10

SAVE AND RESTART #2
ALSO SWITCH TO FULLSCREEN HERE

Continue Cruise

Exterior FPS~80-110
VC FPS~40-60


Top of decent about an hour later

Exterior FPS~40-50
VC FPS~10-15

RESTART #3 HERE.


Decent continues

Exterior FPS ~80-100
VC FPS~40-50

Landing

Exterior FPS ~40-50
VC FPS~18-25

By the time I taxi and reach the gate
Exterior FPS ~20-28
VC FPS ~13-19


If the frames only dropped around airports and such I'd say its just graphics settings, but the drop slowly progresses seemingly no matter what is going on onscreen.

I have repeated the exact flight twice for comparison (only this time FULLSCREEN all the way), with pretty much similar results.



I then flew the flight a third time in the 707 instead..

Exterior FPS on average 70-90
VC FPS on average 40-50


any ideas would be helpful. :-?