The first time that you execute GiD, the following window will be displayed. 
Where you can choose OpenGL working mode and GiD theme.
This options can be found inside GiD in Utilities -> Preferences window
Also it's possible to change OpenGL options by clicking on 
in the bottom right corner of GiD window
Within the program gropu grop GiD it is also installed a small application "Repair GiD" which useful to reset the GiD configuration (some graphic cards and drivers have problems with the hardware option, the screen can show corrupted images or even GiD can crash)
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