My GPU is Mullins, integrated with the GX-412HC system-on-chip. I am running Ubuntu 14.10 with xserver-xorg-video-radeon_7.5.0-1. Video playback through a competent player like mpv is generally smooth even when using the default performance profile, with the default 60hz display mode selected. However, if I use xrandr: xrandr --output HDMI-0 --mode 1920x1080 --rate 24 Suddenly playback becomes quite jerky, and is not helped much by raising the card to the highest performance profile. This is true of VLC, mpv, and mplayer2, so I do not think it is player related. This is also true of any video file. I have tested this with a variety of radeon DRI and xserver-xorg-video-radeon versions. In those versions that support Mullins, I have not seen any differences. Using a 24hz mode is very desirable when playing back a feature film that was shot at 24 fps.
Please attach your xorg log and dmesg output.
Created attachment 114887 [details] Xorg log Yes, I am using display :2.
Created attachment 114888 [details] dmesg output
Additional info: OpenGL is also slowed down significantly. The problem is not limited to VDPAU.
Adam Leggett, Ubuntu 14.10 is EOL as of July 23, 2015. For more on this, please see https://wiki.ubuntu.com/Releases . If this is reproducible in a supported release, it will help immensely if you filed a new report with Ubuntu by ensuring you have the package xdiagnose installed, and that you click the Yes button for attaching additional debugging information running the following from a terminal: ubuntu-bug xorg Also, please feel free to subscribe me to it. For more on why this is helpful, please see https://wiki.ubuntu.com/ReportingBugs.
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