Virtual desktop size setting disables HW acceleration
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| xserver-xorg-video-intel (Ubuntu) |
New
|
Undecided
|
Unassigned | ||
Bug Description
Binary package hint: xserver-
I run Ubuntu 9/04 on a Macbook with the following graphics card:
00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller (rev 03)
00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller (rev 03)
By default everything works fine. Then I plug in an external monitor with resolution 1920x1200. I start the resolution config app and set external monitor's resolution to 1920x1200. I get a popup saying that I need to enable virtual desktop size to xorg.conf. I do that and restart X.
When I log in, xserver has changed to Mesa software rendering. If I go and remove the virtual size setting from xorg.conf, I get DRI HW acceleration, but the external monitor's resolution goes to 1024x768.
So I can either get native resolution OR hw accelerated OpenGl. But not both.
| Geir Ove Myhr (gomyhr) wrote | #1 |
Unfortunately, your chipset (945GM) has a hardware limitation in that it does not support hardware acceleration if the virtual desktop (as defined in xorg.conf) exceeds 2048 in one direction. This usually happens when you use an extended desktop side-by-side. A possible workaround is to place the monitors above one another. This bug is a duplicate of bug 146859.