Cygwin/X causes NVIDIA GPU to turn on in Optimus systems
Wed Mar 27 00:30:00 GMT 2013
I also have nvidia optimus and noticed this problem but with me the
nvidia gpu only kicks in for a brief time whenever a x application is
started, so the extra enery consumed is very small. It is anoying all
the same, I appreciate any workaround for this.
On Tue, Mar 26, 2013 at 12:58 PM, Aaron A. Kelley
> For those that aren’t aware, NVIDIA Optimus is a feature that makes use of
> the Intel GPU that is included in new Intel Core i series processors (Sandy
> Bridge and up). Basically, in a system that has both the integrated Intel
> GPU and also a discrete NVIDIA GPU, the Intel GPU is used for most desktop
> operations and the NVIDIA GPU kicks in when the graphics power is needed for
> games and other processing jobs. This is done to save power --- if the
> NVIDIA GPU can spend most of its time powered down, your battery lasts
> longer. The NVIDIA card can be used to run only particular applications
> individually, and its output is dumped over to the Intel GPU for display
> using some fast framebuffer magic.
> I usually leave Cygwin/X open on my machine because I use it to access GUI
> apps running in SSH terminals from time to time. Today I noticed that in an
> Optimus environment, it is causing the NVIDIA GPU to kick in, which causes
> the NVIDIA GPU to stay powered on when maybe it doesn’t need to.
> I went to the NVIDIA control panel and set xwin.exe specifically to use the
> integrated GPU but it still says that xwin.exe is running on the NVIDIA GPU
> when I run it. Cygwin/X must be doing something unusual at initialization
> that makes the NVIDIA card feel like it has to kick on. I don’t have to
> actually launch any X windows to see this occur, it happens moments after I
> launch the Cygwin/X server.
> I haven’t been able to find anyone else mentioning this. It may be because
> Optimus configurations aren’t very common. This also means that this issue
> may be tricky to track down. I’m not sure if it will be easy to find
> someone who knows about Cygwin/X development who also has access to an
> Optimus environment. This might be something that has to go for NVIDIA for
> them to fix in their drivers, but it’d be nice to know a little more about
> the issue before trying to get in touch with them.
> I’m interested in doing anything I can do help address this but I don’t know
> where to begin, so I’m welcoming your feedback.
> Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
> Problem reports: http://cygwin.com/problems.html
> Documentation: http://x.cygwin.com/docs/
> FAQ: http://x.cygwin.com/docs/faq/
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
Problem reports: http://cygwin.com/problems.html
More information about the Cygwin-xfree