Originally Posted by AaronP
Basically, you're telling the driver to ignore what it thinks the native resolution of your screen is supposed to be and forcing it to use what you tell it instead. This is really only necessary when you have a broken monitor like yours -- DVI monitors are required by the DVI spec to return an EDID, so it's not unexpected to get weird behavior with a monitor that doesn't.
Well, that "broken monitor" of mine is really the secondary display to a brand new Thinkpad worth $4500 and being quoted as officially supported for Linux & NVIDIA.
But now I have a different problem.
After some supposedly unrelated upgrades, my video system stopped working (black screen on startup of X11) and so I had to re-install NVIDIA from scratch.
For that I downloaded the latest driver from the NVIDIA website (NVIDIA-Linux-x86_64-185.18.14-pkg2.run).
After I installed that one, my X11 was up & running again, but now I'm stuck with a "tacky" mouspointer on each screen.
Previously my mouse pointer would just follow along, but now a remnant of that thing allways keeps getting stuck on one screen when I move the mouse cursor to the other.
I googled for this bug and found that is a known issue with the NVIDIA driver and XINERAMA.
I can't use TwinView because of the 90 degree rotation requirement for my secondary display, so I have to use Xinerama.
Switching on the SWcursor option leaves a nasty cursor trail on my secondary display, so how do I get out of this one - I don't have the old driver no more and don't even know which version it was that I used to have installed.