Gamma problems after installing OpenGL

My monitor has been getting darker and darker for a while now. At this point, even with the brightness and contrast at maximum, the screen is only half-lit. I use Adobe Gamma to offset the problem, and my monitor usually looks fine now. But after I updated OpenGL, videos are no longer affected by Adobe Gamma. Videos played by any player are bright for about five seconds after they’re resized, and then turn back to my monitor’s innate gamma setting, ignoring the software gamma boost. Any suggestions?