My 14.04 system also suffers from a variation of this problem. FWIW, I find that the "flicker problem" is tied to the PERFORMANCE LEVEL of my GTX 275. If I watch the GPU from the PowerMizer panel of the "NVIDIA X Server Settings" application, the "flicker problem" appears when the Performance Level drops to 0. At Performance Level 1 or 2, the problem disappears.
By "flicker problem", I mean that the screen erratically switches between a partially-updated display and a fully-updated display. All applications that don't "sufficiently challenge" the GPU, and cause the nVidia Performance Level to climb, suffer from this problem! However, if I run one of my high frame-rate OpenGL programs, the problem disappears, until I exit the application, and give the nVidia driver stack a chance to settle back down to Performance Level 0.
BTW, none of the Compiz tweaks mentioned in this thread, or any other, has helped my situation, only the Performance Level matters. I'm now running nVidia Driver version 340.46, but the problem existed when I was running 331. My system is an "old" LGA 1366 Quad Core i7 with 12GB of memory, and a GTX 275.
My 14.04 system also suffers from a variation of this problem. FWIW, I find that the "flicker problem" is tied to the PERFORMANCE LEVEL of my GTX 275. If I watch the GPU from the PowerMizer panel of the "NVIDIA X Server Settings" application, the "flicker problem" appears when the Performance Level drops to 0. At Performance Level 1 or 2, the problem disappears.
By "flicker problem", I mean that the screen erratically switches between a partially-updated display and a fully-updated display. All applications that don't "sufficiently challenge" the GPU, and cause the nVidia Performance Level to climb, suffer from this problem! However, if I run one of my high frame-rate OpenGL programs, the problem disappears, until I exit the application, and give the nVidia driver stack a chance to settle back down to Performance Level 0.
BTW, none of the Compiz tweaks mentioned in this thread, or any other, has helped my situation, only the Performance Level matters. I'm now running nVidia Driver version 340.46, but the problem existed when I was running 331. My system is an "old" LGA 1366 Quad Core i7 with 12GB of memory, and a GTX 275.