Gentoo ati drm driver in X.org 6.8.2

configuration step:

genkernel --udev --menuconfig all

• Device Drivers - Character devices)
• add Real Time Clock Support
• /dev/agpgart (AGP support)
• Intel
  
• SiS chipset support
• VIA chipset suport
• modify /etc/modules.autoload.d/kernel-2.6
• rtc
• agpgart
• sis-agp
• fglrx

wait for compiling finished...

• ATI-Drivers
• emerge ati-drivers
• emerge ati-drivers-extra (contains testing apps.)
• opengl-update ati

• X.org setting
• fglrxconfig
• do not chose AGPGART support, becasue of already built-in in kernel
• modify BuisID to fit your VGA card in /etc/X11/xorg.conf
  

done....