It is strongly recommended to, before doing any changes to game files at all, make a backup copy of them.

There are many guides and utilities spread across the web, regarding optimization, cleaning, and tweaking for an audio-visual appearance exceeding the game's ultra settings.

Some possible variables aren't listed at all, but default values for them are hard-coded. For some variables it is unknown if the game really uses them. Some variables appear twice in the same section, in which case it's unclear which value is taken into account by the game, though it can be assumed, that this would be the first one. The sections and variables are in no specific order. Also some variables are contained in both configuration files, the Fallout.ini and the FalloutPrefs.ini, where the former determine the default values and the latter the values used by the game when playing it (with one definite and one possible exception: iPresentInterval and iRadialBlurLevel). The variables are organized in sections, with some appearing in more than one section. Some comments are contained, lines starting with.

Variables starting with u: Unsigned integers.

Often used for file references or to display text.

Values are plain text without quotation marks.

Variables starting with s/ S: Strings.

They are composed of the three RGB values (ranging from 0 to 255), divided by commas and without blanks. is also often reduced to 4 or 2 decimal places. The console command SaveIniFiles creates a configuration file, where all these are cut down to 4 decimal places, while the command GetINISetting puts them out with only 2.

Variables starting with f: Floating-point numbers, using up to 6 decimal places.

They can only have the valid values of 0 and 1, where 0 means 'false' or 'disabled', and 1 means 'true' or 'enabled'.

Variables starting with b: Boolean variables.

There are several types of variables, determining the possible values one can have. It normally remains unchanged, though the Fallout: New Vegas version is overwritten with default values each time the game is started via Steam. It is then saved in the user's My Game directory. The Fallout.ini, together with the FalloutPrefs.ini, is created when for the first time the launcher of the game is started.

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