Display only works *after* suspend

view full story

https://bbs.archlinux.org – Hello,I have a problem which seems to be rather strange for Linux laptop problems - I can only get to the desktop through X11 after closing the lid, letting the laptop suspend, and opening the lid again to resume. Before this point, everything through the console works and I can switch to a TTY, but after KDM is started (via systemd) a blank screen appears. This laptop (an HP DV6) has dual cards which cannot be selected between in the BIOS - both AMD, integrated is the HD4200 and dedicated is the HD5650. I am using catalyst from the community repo - I have tried the PowerXpress and normal buil (HowTos)