This must be done on both the boot command line and in the module configuration. /etc/default/grub: GRUB_CMDLINE_LINUX="nomodeset" /etc/modprobe.d/radeon-kms.conf options radeon modeset=0 Seems Debian may not be alone: http://www.google.co.uk/support/forum/p/earth/thread?tid=14d1cfa87364d0c4&hl=en&fid=14d1cfa87364d0c4000486929031f176&hltp=2