After further investigation, I have found an in-kernel tool for switchable graphics called vga_switcheroo.
To use vga_switcheroo, modesetting must be enabled for both drivers. On my kernel command line, I put both
In my rc.local, I have the following:
# Load the Radeon module
# Turn on the dGPU
echo ON > /sys/kernel/debug/vgaswitcheroo/switch
# Make the dGPU the default card
echo DIS > /sys/kernel/debug/vgaswitcheroo/switch
# Turn of the goddamn useless Intel card
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
However, this does nothing! On login, I find that the default video card is still the Intel card:
[fluffypony@0xffeDAEMONPAWNY1969 ~]$ sudo cat /sys/kernel/debug/vgaswitcheroo/switch
When I make the default card DIS by issuing:
sudo bash -c "echo DIS > /sys/kernel/debug/vgaswitcheroo/switch"
The screen freezes. I can still blindly type:
sudo bash -c "echo IGD > /sys/kernel/debug/vgaswitcheroo/switch"
And the screen comes back. Why is this happening?