So I suppose it's the driver version because the problem is gone now. I used this PPA - https://launchpad.net/~ubuntu-x-swat/+archive/x-updates to update the X.Org packages and there the only update that actually matters is the radeon driver version which is 6.13.1.
Solved with: kernel - 2.6.34 final (for Lucid from the mainline Kernel PPA) xorg-server - 1.7.6-2ubuntu7.3 radeon driver version - 6.13.1 Regards, Miro -- [radeon driver] (regression) poor video decoding performance https://bugs.launchpad.net/bugs/578224 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
