How to blacklist radeon module?

2 down vote accepted

I found an easy way:

Open /etc/modprobe.d/blacklist.conf as super user, or create it if it is not there.
Add the following line: blacklist radeon.
Run sudo update-initramfs -u then reboot.

To confirm that the module has been disabled, after rebooting run lsmod, and if radeon is not listed in the output then it has been blacklisted.