AUTOGEN_DENSITY setting in fsx.cfg and autogen slider in FSX settings. How to set it for the best performance and quality?
FSX tweak guide
Effect on performance: yes
Effects on quality: yes
Good for: everyone needs to choose autogen density
AUTOGEN_DENSITY vs Autogen slider
AUTOGEN_DENSITY code in fsx.cfg shows the position of autogen slider in FSX settings.
AUTOGEN_DENSITY=5 – Extremely Dense
AUTOGEN_DENSITY=4 – Very Dense
AUTOGEN_DENSITY=3 = Dense
AUTOGEN_DENSITY=2 – Normal
AUTOGEN_DENSITY=1 – Sparse
AUTOGEN_DENSITY=0 – None
Each step takes out 20% of autogen.
How it works?
Just set the slider or change fsx.cfg value (remember that changing FSX settings may change some of fsx.cfg tweaks so it’s safer to make your changes directly in the file).
Effects on performance
Dense autogen may have adverse effect on FSX performance. The effect changes with the location and the scenery you use.
A modern (2015) PC should have no problems running default FSX scenery at Extremely dense setting (AUTOGEN_DENSITY=5).
If you use add-on sceneries adjust density setting to your scenery and to the place where you fly. Extremely dense autogen causes no harm over desert but may crash your FSX when flying over Canadian forests.
Effects on quality
View gets better as the density grows.
For payware sceneries i recommend using the following settings:
High-end PCs (quad core @ 4.5GHz+, 8-16 GB RAM, nVidia 770 or better): AUTOGEN_DENSITY=5
Mid range PCs (quad core @ 3.8-4.5GHz, 8-16GB RAM, nVidia 660 or better): AUTOGEN_DENSITY=4
Low-end PCs (quad core 3.8GHz or slower, dual core, nVidia 550 or earlier): AUTOGEN_DENSITY=2 or 3
There are basic settings that should be adjusted for scenery requirements and possibly – the weather. In some cases AUTOGEN_DENSITY=5 will be out of range even in the best PCs (because of OOM risk in 32-bit application like FSX).
Low-end PCs may run autogen at AUTOGEN_DENSITY=4 without a problem if the scenery allows it and if other factors affecting performance are not at play.
After years of tests on several different PCs I can say that AUTOGEN_DENSITY=4 is the safest setting and gives an acceptable autogen density.
If you use default scenery – add 1 to the settings above. For freeware sceneries – sometimes it’s safe to add 1, sometimes you need to lower the setting.
The lower the better… NO!
It’s tricky how the autogen causes performance problems but my observation is that in many cases the difference between sparse and very dense autogen can be negligible. If you look for performance boost – make sure that you aim in the right direction.
If you experience FPS drops flying in bad weather – changing autogen to sparse will probably make no difference – resources released will be too small to cause better FPS.
On the other hand – if the problems increase when you are close to a large city or a forest – you should adjust autogen settings.
Adjust for the scenery
I fly at AUTOGEN_DENSITY=5 or AUTOGEN_DENSITY=4. But there are a few sceneries where I go as low as 3 (Dense). It happens mostly over freeware sceneries that use unoptimized autogen and over some payware sceneries where autogen is too “heavy”.
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