I did it! Finally I'm able to boot linux-rt with working (but proprietary) fglrx drivers. I used kernel versions 2.6.27-7 and 2.6.27-3-rt from the repos. Here's a Howto for everyone who also spend hours of frustration: 0. Uninstall the fglrx driver and linux-rt if installed. 1. Last night I found https://launchpad.net/~abogani/+archive . There's a subfolder "fglrx-installer". Download those debs (fglrx-amdcccle_8.543, fglrx-kernel-source_8.543, fglrx-modaliases_8.543, libamdxvba1_8.543, xorg-driver-fglrx_8.543, xorg-driver-fglrx-dev_8.543) and install them. Neither mess around with those other files like "fglrx-installer", I didn't need them, nor add the repository to your list (also not needed, linux-rt won't even install if you do that). If the files mentioned above aren't there, email me. 2. Just install linux-rt, image, headers, restricted modules in synaptic - watch for the dkms message! If fglrx was succesfully build in your standart kernel, it should automatically install for the linux-rt kernel. In my case it was confused because there was fglrx 8.552 and fglrx 8.543 installed, I had to remove version 8.552 in order to get it to build (sudo dkms remove -m fglrx -v 8.552 --all). If dkms in the details dialog in synaptic says it's alright you should be fine. I'm so happy, I'm going to post this on ubuntuusers.de and the proprietary ati driver wiki. Cheers! Matthias