12th February 2017, 13:56
glxgears ist not a benchmark application. It is just a test for 3D Mesa Graphics.
60FPS is the refresh rate (VSYNC) you probably have on your desktop
As 3D is running fine it does not seem to be a general driver issue that freezes your box with the nouveau driver.
It might be still that some special 3D instructions that the driver says are supported for your card either aren't or will freeze on your hardware.
This is indeed not very easy to debug as it seems there is some other issue with your tower pc as it is freezing up no matter which graphics driver you use.
So there might be something else interfering aswell.
What you could try is installing another newer vanilla linux kernel. See this wiki entry with a lot of information on how to do this: https://wiki.ubuntu.com/Kernel/MainlineBuilds
I would try using one of the newest LTS Kernels, like 4.9.9 first and see if it fixes the issue on your hardware.
60FPS is the refresh rate (VSYNC) you probably have on your desktop
As 3D is running fine it does not seem to be a general driver issue that freezes your box with the nouveau driver.
It might be still that some special 3D instructions that the driver says are supported for your card either aren't or will freeze on your hardware.
This is indeed not very easy to debug as it seems there is some other issue with your tower pc as it is freezing up no matter which graphics driver you use.
So there might be something else interfering aswell.
What you could try is installing another newer vanilla linux kernel. See this wiki entry with a lot of information on how to do this: https://wiki.ubuntu.com/Kernel/MainlineBuilds
I would try using one of the newest LTS Kernels, like 4.9.9 first and see if it fixes the issue on your hardware.