I have set up a Ubuntu package repository for development versions of Xorg components (see https://wiki.ubuntu.com/XorgOnTheEdge). This can be used from a Ubuntu live CD, to safely test without modifying your normal installation.
1. Boot from a Ubuntu 9.04 Desktop CD (http://www.ubuntu.com/getubuntu/download). To save fossil trees, please use a bootable USB stick instead of burning CDs. Run "usb-creator" to install the ISO image onto your USB stick, or see for instance https://help.ubuntu.com/community/In...n/FromUSBStick for the hard way.
2. If you use wireless networking etc, get connected to internet.
3. Download the xorg-edgers-live-test script from https://wiki.ubuntu.com/XorgOnTheEdge (if you haven't already copied it to your USB stick)
4. Only for using the radeonhd driver:
Run the commandor edit the xorg-edgers-live-test script and uncomment the corresponding line in the script. If radeonhd is installed, it will be picked instead of radeon.Code:sudo apt-get install xserver-xorg-video-radeonhd
3. Switch to a virtual console with Ctrl-Alt-F1
4. Runif you copied it to your USB stick, or if you just downloaded it:Code:sudo sh /cdrom/xorg-edgers-live-test5. Sit back and breath calmly, and watch while your computer loads and fires up fresh Xorg goodies.Code:sudo sh ~/Desktop/xorg-edgers-live-test
Note that the package repository is updated more or less regularly, and things might break. That's the nature of development versions.
EDIT: updated to 9.04