Comment 9 for bug 1007857

Revision history for this message
Scott Deagan (scott-deagan) wrote :

I am now running Ubuntu 12.10 and am experiencing the same problem. I have a desktop PC with an FM1 motherboard and AMD A8 3850 APU. I have two graphics cards and swap between them - an nVidia GTX 460 and an AMD Radeon 7870. I have tried several drivers for both of these graphics card (on the nVidia side, everything from 285.xx onwards, and for the AMD Radeon everything Catalyst 12.8 to 12.11 beta).

I have tried the following:

1. Unchecking "Detect Refresh Ratge" and setting the refresh rate manually (several values, including 60, 120 and 180).
2. Setting "Force full screen refraws (buffer swap) on repaintg" in workarounds.
3. Setting "CLUTTER_PAINT=disable-clipped-redraws:disable-culling" in /etc/environment.
4. Using edgers PPA and x-swat for latest/experimental packages.
5. Several other things I can't even remember now.

Some of my observations (Ubuntu 12.10, wobbly windows enabled):

1. Yesterday, when the Google logo was a JavaScript game, dragging windows around was stuttery when FIrefox was opened and on the Google homepage.
2. Things are smoothest when running in 1920 x 1080.
3. When I turn up the resolution to 2560 x 1440, dragging wiindows around in the centre area of the screen is smooth, but if I drag a window close to the top of the screen or near the Unity Launcher, the movement will be stuttery (this doesn't happen in 1080p).
4. Problem (stuttering) is exacerbated when running two monitors.
5. SuperKey + S to show virtual desktops always jerky/stuttery.
6. SuperKey + W to show all windows always jerky/stuttery.

Here's the kicker: on my laptop which has Intel HD 4000:

1. Just about everything works perfectly - the smoothest animations and window movement I've ever seen on Linux.
2. Dual monitors worked by simply plugging in an external monitor via mini DisplayPort.
3. Dragging windows still buttery smooth in dual monitor configuration (1080p and 1440p).
4. SuperKey + W to show all windows is buttery smooth at 2560 x 1440.
5. SuperKey + W to show all windows is jerky when running two monitors (one monitor at 1080p, the other at 1440p).
6. SuperKey + S to show all virtual desktops buttery smooth on single monitor running at 2560 x 1440 (1440p).
7. SuperKey + S to show all virtual desktops jerky/stuttery for dual monitors (1080p and 1440p).

It seems strange that running Ubuntu 12.10 with my nVIdia 460 or Radeon 7870 on my desktop PC results in jerky/stuttering animations and window dragging, yet using my laptop with integrated Intel HD 4000 graphics everything is buttery smooth, pixel perfect and responsive (when using a single monitor). The difference in the end-user experience is truly like night and day. I wish I could somehow run Compiz with my laptop's nVidia 650m using "optirun" (Optimus) to see if animations/dragging windows was still smooth. If it was, then the nVidia proprietary drivers could be ruled out, and the culprit could be something to do with the AMD chipset (my desktop is an AMD A8, my laptop is an Intel core i7). Next pay cheque (in a couple of weeks) I will purchase an Intel motherboard and CPU for my desktop to see if that makes a difference.