The flickering bug described in the following was fixed. If you don’t want to wait until it has been released officially, get the deb packages at launchpad:
After installing you should be able to use the driver with the default EXA acceleration method again. If you’ve changed anything at the xorg.conf to avoid the flickering, don’t forget to reset your xorg.conf after installing the fixed driver.
For the sake of completeness, here is the old workaround:
When I had installed the new Ubuntu release on my notebook (HP Compaq 6715b), I was so happy about the fact, that most problems which had occured with the notebook drivers finally disappeared in Jaunty. But that feeling didn’t last long.
Broadcom WLAN-Chip with WPA2 worked – YAY!, Standby and Hibernation worked – YAY!
But, what’s that? Flickering black and red stripes around the middle of the screen, flashing white stripes and more flickering when scrolling the terminal. OpenGL apps also flicker and display the windows behind the OpenGL window for a split second now and then.
Unfortunately ATI moved the drivers for the graphic chipset ATI Xpress 1250 to their „Legacy“ program. They discontinued their proprietary driver support several months ago. BOOOO!! Tragically Jaunty comes with the new Xorg 7.4, which is NOT supported by this legacy driver. NO!
Sadly x1250 users have to use the free radeon driver coming with ubuntu.
Ok, let’s set it up to remove the flickering and display problems!
- Turn off Compiz completely (System -> Settings -> Appearance -> Visual Effects). This will remove the first problems.
- Change the „Accelleration Method“ from EXA to XAA. Edit your /etc/X11/xorg.conf and add the following line to your Device section:
Option „AccelMethod“ „XAA“
This will remove the rest of the display problems.
- Restart Gnome in a clean way. First logout in Gnome, then Switch with Ctrl+Alt+F1 to a shell and do a sudo /etc/init.d/gdm restart
- Problems should be gone now
I couldn’t figure out any difference in perfomance after switching the AccelMethod to XAA. But neither EXA nor XAA can’t control the x1250 chipset as the proprietary driver of ATI did. It’s pretty slow and it seems that the free driver handles the chipset not correctly, because the system temperature is higher now and the notebook fan is nearly always activated.
I hope now, that there will be a better free driver of this chipset soon. And I also hope, that I could help you a little bit in how to get rid of the display problems with the free graphic driver radeon and the x1250 chipset.
Any new ideas or news are welcome!
Keywords: flickering, red black, display problems, X1250, Xpress1250, ATI, white stripes, compiz, desktop effects