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I'm running Ubuntu 15.04 on a laptop with an Intel HD Graphics 5000 and a nVidia GeForce 520M, joined by an Optimus. I'm trying to upgrade my graphics drivers to the latest provided by the vendor so I can use the new experimental build of Unity 3D.
However, when I try switch to any driver besides the default open source one,
glxinfo gives me this error:
X Error of failed request: BadValue (integer parameter out of range for operation) Major opcode of failed request: 154 (GLX) Minor opcode of failed request: 24 (X_GLXCreateNewContext) Value in failed request: 0x0 Serial number of failed request: 33 Current serial number in output stream: 34
...and then when I reboot, my graphics don't work, so I have to revert to the old drivers via the command line. The thing is, I've been able to use Optimus on this laptop before (via