FSX Tweak Of the Week-FIBER FRAME FRACTION

For additional tweaks visit
www.highflightsimulations.com

The "FIRST" and "FOREMOST" thing to remember before applying any "tweak" in Flight Simulator X is always remember to backup your important files first! Should your "tweaking" attempt fail, you will always have the original files to revert to, thus preventing a complete de-install and re-install of Flight Simulator X. There are several files and folders that you will need to backup first. These files and folders are listed in the following sections. I recommend copying these folders to DVD-RW's. The first place to start is by modifying the FSX.cfg file. Many people are intimidated by modifying this file, but not to worry. If you backed-up your file, let's get started.

Double-click on the FSX.cfg file (for the location of this file, see the text below). If you are prompted to select a program to open the file, select "Notepad".

The sections in the FSX.cfg file are categorized by sections stated in brackets.
i.e. [MAIN]

FILE/FOLDER NAME: FSX.cfg file

FSX.cfg File Locations

WINDOWS VISTA USERS:
Located in Desktop\[Your Computer Name]\AppData\Roaming\Microsoft\FSX\fsx.cfg

WINDOWS XP USERS:
Located in C:\Documents and Settings\[Your Computer Name]\Application Data\Microsoft\FSX\FSX.cfg
* = This file may reside on a different drive.

This file can only be accessed by opening your "Computer" (Windows Vista) or "My Computer" (Windows XP), then clicking on the "Tools" tab, then "Folder Options", then "View". Make sure that you have checked the box next to "Hidden Files and Folders" and "Show Hidden Files and Folders".

Tweak #1 - Fiber Frame Fraction
To reduce this cause of the blurries, Microsoft has reworked how Flight Simulator X scheduler prioritizes background tasks in FSX. Now much more CPU time is devoted to loading scenery data, including terrain textures, at the expense of somewhat lower frame rates. In my opinion, this change has mostly solved this cause of the blurries, although the scenery loader can still get behind at extremely low frame rates (less than 10 fps) or at very large airspeeds (faster than 600 knots). There are several ways to adjust how much CPU time FS devotes to loading scenery and textures. The easiest way is to set the target frame rate slider to a value that your machine can consistently achieve. The lower you set the slider, the more CPU time is diverted from rendering to loading data. Another thing you can do is to modify the following variable in FSX.CFG:

FIBER_FRAME_TIME_FRACTION=n
[ n = 0.01 - 0.99 ]

This variable determines the amount of CPU time given to loading scenery data as a fraction of the time spent rendering. For example, the default value of 0.33 means that for every 3 milliseconds spent rendering, FS will give 1 millisecond to the scenery loader. If necessary, you can use a larger value to devote more time to loading (any number between 0.01 and 0.99). Or, if you don't have a problem with the blurries and you want slightly higher frame rates, then you can use a smaller value.

Should you choose to use this "tweak", here's how to do it: Insert a line directly under the [MAIN] section and enter

FIBER_FRAME_TIME_FRACTION=0.33

Experiment with the number entered here and adjust them to your taste for a balance of quality & speed. It has been reported that for true photo scenery depending on your PC specifications, you may need to set this value as high as(0.50 or even 0.66.)

* * * For Dual Core Users * * *
The setting of 0.01 - 0.20 will allow you to have your AutoGen set to "Very Dense" and maintain a Frame rates of 20 - 100 FPS rate (depending on your area of flight - FPS will be higher in rural areas and lower in large cities).

The recommended setting:

FIBER_FRAME_TIME_FRACTION=0.70