Now onto the different Nouveau issues uncovered when trying out Linux 3.13 and Mesa 10.1-devel...
The NVIDIA GeForce GTX 650 graphics card was running fine at first, but after a while during the OpenGL performance testing the screen stopped responding and from a virtual terminal it was spewing Nouveau DRM driver errors. These GTX 650 issues came down to "failed to idle channel" error messages.
With a variety of different GeForce 9 series graphics cards tested is where problems seemed quite common. The GeForce 9 graphics cards tested -- 9800GTX, 9800GT, 9500GT, et al -- would end up passing the graphics cards tested but at the end and beginning of new tests it was common for a lot of on-screen corruption.
The OpenGL game where most of the on-screen corruption would take place was Xonotic for the different GeForce 9 GPUs.
With the NVIDIA GeForce 9600GSO graphics card, some PGRAPH errors were also discovered when running various benchmarks.
When testing the GeForce 9500GT while running Unigine Sanctuary, once every few minutes the screen would turn yellow and/or red for a few frames, but the test finished fine and there was only the brief interruptions.