ATI Technologies RADEON 8500 User Manual page 14

Clicking the Game Gamma button accesses the
Game Gamma Properties.
Red Green
Blue sliders
RGB Lock
Defaults
button
Game Gamma Properties
These controls allow you to increase or decrease the
color brightness of Direct 3D and OpenGL games
played in fullscreen mode. (NOTE: Game Gamma is
NOT supported in Windows NT4.0)
Uncheck this to adjust the RGB sliders individually.
Check this to adjust all three sliders at the same time.
This allows you to reset the Game Gamma settings to
default values.
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