Hallo!

My card (Radeon M9) doesn't permit dri if I have dual screens. Maybe if you check /var/log/Xorg0.log you'll see a similar warning.

Thanks, I also have a ATI radeon:

holzi@holzi:/var/log$ cat XFree86.0.log | grep DRI (II) Loading extension XFree86-DRI (WW) RADEON(0): Direct Rendering Disabled -- Dual-head configuration is not working with DRI at present.

google says: The dri driver (ATI) does not support dual-head and 3d acceleration at the same time. If you're feeling adventurous, you should be able to get this to work with a patch, as long as both your screens don't exceed 2048 pixels in one dimension.

But anyhow, I don't need it in the moment, I will try it when I need it ... :)

LG Georg