Diamond Multimedia 7500 User Manual

Clicking the Game Gamma button accesses the 
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.