Comment 2 for bug 291480

About the driver I do use,
:~$ glxinfo | grep render
IRQ's not enabled, falling back to busy waits: 0 16
direct rendering: Yes
OpenGL renderer string: Mesa DRI R200 20060602 AGP 8x x86/MMX+/3DNow!+/SSE TCL

I just've installed Ubuntu 8.10 without modification (I installed the normal multimedia codecs and also, for Firefox, the Flash player plugin and Java, to see web videos).

The result of fglrxinfo it is (in Spanish):
:~$ fglrxinfo
El programa «fglrxinfo» puede encontrarse en los siguientes paquetes:
 * xorg-driver-fglrx
 * xorg-driver-fglrx-envy
Pruebe: sudo apt-get install <paquete seleccionado>
bash: fglrxinfo: orden no encontrada

So I don't have installed fglrxinfo.

The glxgears output with the default video settings (I guess you refer to the FPS using glxgears command):

:~$ glxgears
IRQ's not enabled, falling back to busy waits: 0 16
4734 frames in 5.0 seconds = 946.634 FPS
5280 frames in 5.0 seconds = 1055.868 FPS
5323 frames in 5.0 seconds = 1064.454 FPS
5309 frames in 5.0 seconds = 1061.649 FPS
5301 frames in 5.0 seconds = 1060.191 FPS
5285 frames in 5.0 seconds = 1056.930 FPS

Otherwise, the output of the video, as you advise, it's:
~$ glxgears
IRQ's not enabled, falling back to busy waits: 0 16
4480 frames in 5.0 seconds = 895.928 FPS
5265 frames in 5.0 seconds = 1052.914 FPS
5306 frames in 5.0 seconds = 1061.022 FPS
5365 frames in 5.0 seconds = 1072.865 FPS
5326 frames in 5.0 seconds = 1065.139 FPS
5249 frames in 5.0 seconds = 1049.729 FPS

Before that, trying to get better video performance I have installed DRIconf and I've set up all its settings to the minimum: minimum image quality, minimum texture units (2), using HiperZ to enhance performance, etc. all of which has been a bit helpful as before that the frames in 5.0 seconds didn't go higher than 4200 or so (at its best). Now the OS goes notably faster, scrolling the windows not longer lag.

But the videos still had a quite poor FPS, the video buttons mostly don't respond when full size video is displaying (about 3 seconds delay to respond since clicking on stop or when trying to change volume.. Sometimes even fail to respond and so one has to click several times).

With the gstreamer-properties set to W windows (without Xv) perhaps the Youtube videos go slightly faster.. The sliding bar for the volume and the other buttons it lag (just) about 2 second now. The images go also a bit quicker, but not smooth. And still each few seconds the image freezes for an instant at its own or when passing the mouse over (or trying to click) a button.