I just finished my Gentoo minimal install and the first thing I wonder is why I get no picture. I did have signal on the live CD, so that was pretty odd. I plugged the monitor into the Intel HD Graphics HDMI output instead, and there was my picture.
There's just this issue, I have 3 monitors. I need the AMD drivers, so I go ahead and install the proprietary ones, because I have the best experience with those. In order to do that, I had to recompile the kernel with some settings off and on to enable the AMD KMS. I have no idea what it is, but it worked fine following this guide (for my Sapphire Radeon HD 7970).
I'm aiming to install XFCE 4, so I also had Xorg installed.
emerge xorg-server ati-drivers
startx and got the picture I expected on the monitor plugged into the Intel HD port. Now I stopped the x-server again and ran
aticonfig --initial and rebooted. I already know that aticonfig only updates xorg.conf and when I started x again it appeared on the correct monitor. The only thing bothering me now is that the CLI before starting x is STILL on the integrated graphics monitor. How do I get this sent to the dedicated graphics card as well?