I'm having trouble with my graphics setup under linux. My system has two GPUs, one onboard and a dedicated card. It's one of those AMD Liano (?) Systems, with an "APU" (Processor incl. GPU). The dedicated card is also a Radeon (the reason behind this setup is the "Dual Graphics" feature, but that's not what i'm trying to get to run under linux). I'm using the open source radeon module, not fglrx.
My Monitor is connected to the dedicated card and the BIOS recognizes this as the primary screen. But when i'm booting linux, the radeon module seems to switch to the onboard GPU as its primary display (the on board VGA adapeter seems to become the display where vconsoles are displayed at, even if nothing is connected). The screen conneced to the dedicated card will stay blank (not off, just blank!). So the screen will be unusable as a vconsole, but X will work correctly.
I've tried to disable all unwanted outputs by adding video kernel parameters (e.g. video=VGA-1:d), setting the mode explicitly, which changed nothing at all. Is there a way to pick a screen/gpu for the vconsole, or a way to deactivate the onboard card (i can't to that in the BIOS and also need the card for windows). Or maybe just deactivating the KMS for the onboard card.
One workaround for now is just to live without vconsoles and stick with X. If I try to switch to a vconsole from X, the cursor just disapears but the display stays in X.
Some Info: I'm running Archlinux with a 3.4.6 Kernel.