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As the title says, I am having some pretty bad screen tearing issues on the desktop in Ubuntu 14.10, with both the latest fglrx-updates and fglrx drivers on a Dell Latitude E6540 with a Radeon HD 8790M GPU.

From what I understand, this GPU sends its output to the screen through the Intel card's framebuffer, if that is of any significance. I am using the laptop's built-in 1080p screen, and running regular Unity with no modifications. I have not tried any external monitors, but from what I've read, the dedicated GPU can only output directly to a monitor through the docking station ports, and I do not have a docking station with me right now. I imagine the result will be the same as on the laptop's screen.

I have checked the Catalyst control center, and the option to enable V-sync is greyed out and stuck on the second notch (Off, but applications can enable). Games have no noticeable tearing, but the desktop is an ugly mess. Google Chrome even more so; whole blocks of the page will randomly be in the wrong place while scrolling. WebGL pages like acko.net work fine, though, with no tearing.

In Windows, there are no issues, and from what I can tell it will use the integrated GPU until you start a GPU-intensive program like a game, upon which it will switch to the dedicated GPU automatically. In Ubuntu it appears that you can only use either the dedicated or integrated GPU, with no automatic switching like in Windows.

I have attempted to switch the switchable graphics option to "Rendering and additional displays", but upon reboot it switches back to "rendering only".

If anybody has a solution for this, I would be very grateful.

EDIT: To clear things up, there are no desktop, display, or "tear-free" options or sections in CCC. The only option there is the aforementioned greyed out "wati for vertical refresh" option that is set to off.

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  • If you do stumble upon an answer, please post it! I've had the same really bad tearing as you for awhile now, also with Chrome making it really obvious. From what I've read it seems the proprietary fglrx/fglrx-updates drivers are still pretty buggy, so I plan on going back to the default open source driver (giving up some potential 3D performance in exchange for 2D stability). Apr 24, 2015 at 17:09
  • The shabby aspect of this is that version 14.20, a beta, had a tear-free option that actually worked, but for some reason it has never been seen since. Feb 2, 2016 at 11:51

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