FSX.cfg tweaks
Posted by webmaster on January 11 2011 13:12:27
FSX has to be one of the most customizable versions of MS FS ever. This is a great thing for the techy types who are accustomed to making tweaks behind the GUI. On the other hand, those that are less inclined to “monkey” with anything outside the usual set of sliders within FSX are potentially missing out on some great enhancements … and we need all the tweaking we can get! These tweaks can be made in the FSX.cfg file.
Where is the FSX.cfg file?

On Win XP, you’ll find it here: C:\Documents and Settings\username\Application Data\Microsoft\FSX. In Windows Vista & 7, you will want to make sure hidden files are shown and then look here: C:\Users\username\AppData\Roaming\Microsoft\FSX. Sometimes you will not be able to save any changes to the .cfg file in Win 7. Do this: Press the windows key, type in notepad, right click notepad, run as administrator, open the .cfg file in notepad, make changes, save.

Note: Before doing any modifications to the FSX.cfg, make sure to create a back up copy of it.
[MAIN] Tweaks

Under the [MAIN] section of the FSX.cfg file, add the following:
FIBER_FRAME_TIME_FRACTION=0.33
This gives more processing time towards scenery versus rendering and helps to reduce the blurries.

The perfbucket setting adjusts autogen detail level. Setting a lower level gives better performance.
PERFBUCKET=n where n=0 – 7
Default value is 6. Recommended value is 4.

If you wish to disable the pre-load of the default flight when FSX starts up, add this:
DISABLEPRELOAD=1
[DISPLAY] Tweaks


You can disable the notifications that appear on the screen when you engage brakes, etc. Change the following values to show:
InfoBrakesEnable=False
InfoParkingBrakesEnable=False
InfoPauseEnable=False
InfoSlewEnable=False
InfoStallEnable=False
InfoOverspeedEnable=False


You may notice when panning around the virtual cockpit that it takes quite a bit of time to move around. You can speed that up by adding this:
PANRATE=200

If you have a multi-core processor, you can adjust this setting to take more advantage of the extra calculation power:
TEXTURE_BANDWIDTH_MULT=n (n=30-40 for dual core, 70-90 for quad core)
[TERRAIN] tweak


A big difference between FS9 and FSX was the radius in which autogen scenery was to be drawn, and that consumes quite a bit of processing power to provide, thus affects frame rates. Microsoft gave us the ability to reduce that radius that does not significantly impact the experience. In the [TERRAIN] section, add these:
TERRAIN_MAX_AUTOGEN_TREES_PER_CELL=1000
TERRAIN_MAX_AUTOGEN_BUILDINGS_PER_CELL=800

[GRAPHICS] tweak

Those of you who benefit from a cutting edge graphics card that has 1 Gig+ RAM onboard will be able to benefit from the following tweak more so than others. There are some recent add-on’s that employ ultra high resolution graphics (2048×2048 and 4096×4096). With this setting, you allow the full resolution to be experienced in-game.
TEXTURE_MAX_LOAD=4096 (for 4096×4096 textures)
TEXTURE_MAX_LOAD=2048 (for 2048×2048 textures)

TEXTURE_MAX_LOAD=1024 (default value when global texture resolution is set to very high)
Experimentation required

None of the setting suggestions are perfect for your individual set-up. I recommend making minor adjustments to get the performance versus experience to your liking. Enjoy!