I made an entertaing discovery today, my system specs are as follows:

Pentium IV 1.7 Ghz
512 MB Ram
Bog standard 60GB Hard drive
Windows XP on C drive
FS9 on D Drive
GeForce FX5600 256Mb Graphics
Drivers 5.6.7.2 from Nvidia website
AA settings and Anisotropic filtering set by card at 4X and 2X respectively.
Image setting at High Performance
Vertical sync off

Terrain Mesh, Texture and Detail at 100%
Water Effects None
Complexity Normal
AutoGen Normal

No Texture blending
No Extended Textures

Sight Distance 60 Miles
Cloud Draw Distance 40 Miles
3D Cloud Percentage 30
Cloud Coverage density Maximum
Detailed Clouds
1024*768*32
FPS locked to 50

With those settings I get about 19-25 FPS in Cockpit (2D)
16-20 in 3D

If I hit W once to reduce the cockpit down to just the basics it shoots up to 30-40 FPS.  The interesting (to me at least) part of this is that it seems that frame rate is far more dependant on cockpit complexity than Scenery complexity.

I would be interested to find out if others have the same thing happening, after all the Sim has far more to do if it is altering 10-15 guages instead of just 5-6 guages.

Will

AMD AThlon XP 2k
512MB DDR RAM
7200rpm 40GB HDD
Windows XP on Drive C
FS9 on Drive C
ATI Radeon 9600xt Fireblade 128MB
Official Catalyst 4.3
4xAA, 4xAF
Image setting Max Quality
V-sync off


Terrain Mesh, Texture and Detail at 100%
Water Effects High
Complexity Max
AutoGen Max

Yes Texture blending
Yes Extended Textures

Sight Distance Max
Cloud Draw Distance 50 Miles
3D Cloud Percentage 50
Cloud Coverage density Medium
Detailed Clouds
1024*768*32
FPS locked to 30

With those settings I get about 30 FPS in Cockpit (2D)
30 in 3D.  It stays at 30fps when i press W.