** Description changed: The problem here is that incorrect information from the NVIDIA driver is tricking some software like Compiz into using an incorrect refresh rate, which makes the whole desktop look choppy. - The cause of this framerate problem is the DynamicTwinView feature of the NVIDIA graphics driver. It appears to be a documented "feature" of the driver, and has been for several years: - http://us.download.nvidia.com/XFree86/Linux-x86/280.13/README/xconfigoptions.html - (Search for: DynamicTwinView) + The cause of this framerate problem is the DynamicTwinView feature of + the NVIDIA graphics driver. It appears to be a documented "feature" of + the driver, and has been for several years: + + --- Quote from the NVIDIA documentation --- + Option "DynamicTwinView" "boolean" + Enable or disable support for dynamically configuring TwinView on this X screen. When DynamicTwinView is enabled (the default), the refresh rate of a mode (reported through XF86VidMode or XRandR) does not correctly report the refresh rate, but instead is a unique number such that each MetaMode has a different value. This is to guarantee that MetaModes can be uniquely identified by XRandR. + When DynamicTwinView is disabled, the refresh rate reported through XRandR will be accurate, but NV-CONTROL clients such as nvidia-settings will not be able to dynamically manipulate the X screen's MetaModes. TwinView can still be configured from the X config file when DynamicTwinView is disabled. + Default: DynamicTwinView is enabled. + --- End quote --- + [http://us.download.nvidia.com/XFree86/Linux-x86/280.13/README/xconfigoptions.html] WORKAROUND: (in /etc/X11/xorg.conf) Section "Device" Option "DynamicTwinView" "False" EndSection ORIGINAL DESCRIPTION: Binary package hint: xorg My Samsung SyncMaster 931BF does actually support 75 hz screen refresh rate, but xorg lets me choose only between 50 Hz and 54 Hz. Modification of /etc/X11/xorg.conf does not help. xorg worked ok on edgy. Here's some info: $ uname -a Linux Xel-Naga 2.6.20-10-generic #2 SMP Mon Mar 12 00:02:49 UTC 2007 i686 GNU/Linux $ apt-cache show xorg | grep Version Version: 1:7.2-0ubuntu7 The video card is Nvidia GeForce 7300GS. ProblemType: Bug Architecture: i386 Date: Thu Mar 15 21:08:22 2007 DistroRelease: Ubuntu 7.04 Uname: Linux Xel-Naga 2.6.20-10-generic #2 SMP Mon Mar 12 00:02:49 UTC 2007 i686 GNU/Linux
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/92599 Title: Incorrect (low/stuttering) refresh rate with NVIDIA driver To manage notifications about this bug go to: https://bugs.launchpad.net/nvidia-drivers-ubuntu/+bug/92599/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
