I'm running a Radeon HD 6570 in "crossfire" with my A8-5600k APU. However, the AMD catalyst control center for linux does seem to have an option for enabling dual graphics. Does anyone have any experience with dual graphics in Linux? I don't plan on doing any serious gaming from Linux yet, so just the APU is enough for me at the moment, but the time may come when I want to ditch Windows all together.
BTW I just wanted to say thanks to you guys for making such a good resource that gave me the confidence to go ahead and jump on the Linux bandwagon. It's fitting that I'm making my first post on TekSyndicate from my new Linux OS.