Hi, 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 <[email protected]> wrote: > 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. > > http://stuff.aaron-kelley.net/2013/03/cygxoptimus.png > > 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. > > Thanks, > > -- > Aaron > > > -- > 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 Documentation: http://x.cygwin.com/docs/ FAQ: http://x.cygwin.com/docs/faq/
