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I am using ubuntu (well, kubuntu to be precise) and my KDE desktop feels slow. Scrolling is especially slow in kate, windows switching is slow, firefox is REALLY slow.

I have direct rendering enabled using the r300 driver, which has been setup automatically by the installer. The computer is a bit old, but it used to be quite fast at the times I could use the proprietary ati-drivers (which dropped support for my card).

How can I test if there is something misconfigured? I used to use xglgears for that, but it outputs the code below:

Running synchronized to the vertical refresh.  The framerate should be
approximately the same as the monitor refresh rate.
300 frames in 5.0 seconds = 59.872 FPS

Is there anything I can do, or should I just change the video card? Anything you could recommend?

share|improve this question
up vote 3 down vote accepted

In my experience, changing to raster rendering vastly improved KDE4s speed and responsiveness. do this:

sudo apt-get install kde-config-qt-graphicssystem

and then find qt rendering settings in systemsettings. Select raster and logout/back in.

share|improve this answer
Thanks for the suggestion, will try that tomorrow (now I am away from that computer) – Palantir Apr 11 '11 at 6:24
also, you want vSync to be disabled in the effects section of systemsettings, and you want the video memory mode (I think that is what it is called) set to shared, not texture from pixmap. – nerdy_kid Apr 11 '11 at 18:22

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