Counter Strike 1.6 - Unable to play in Open GL
Issue
When I try to launch Counter Strike 1.6 in OpenGL mode, half of my screen turns black. The game works fine in Direct3D mode, so what could be the problem?
Solution
Normally your screen is calibrated at 60 hertz, just change it to 75 Hz when running Counter Strike in OpenGL mode and also adjust your screen resolution.
See also
Knowledge communities.