/etc/bumblebee/bumblebee.conf

[bumblebeed]
VirtualDisplay=:8
KeepUnusedXServer=false
ServerGroup=bumblebee
TurnCardOffAtExit=false
NoEcoModeOverride=false
Driver=radeon

## Client options. Will take effect on the next optirun executed.
[optirun]
# The method used for VirtualGL to transport frames between X servers.
# Possible values are proxy, jpeg, rgb, xv and yuv.
VGLTransport=proxy
# Should the program be run even if the Bumblebee daemon or discrete video card
# is not available?
AllowFallbackToIGC=false


# Driver-specific settings are grouped under [driver-NAME]. The sections are
# parsed if the Driver setting in [bumblebeed] is set to NAME (or if auto-
# detection resolves to NAME).
# PMMethod: method to use for saving power by disabling the discrete video
# card, valid values are:
#        auto - automatically detect which PM method to use
#    bbswitch - for nvidia and nouveau, recommended if available
#  switcheroo - vga_switcheroo method, nouveau and radeon only
#        none - disable PM completely
# https://github.com/Bumblebee-Project/Bumblebee/wiki/Comparison-of-PM-methods

[driver-radeon]
# Module name to load, defaults to Driver if empty or unset
KernelDriver=
PMMethod=switcheroo
# colon-separated path to the nvidia libraries
LibraryPath=
# comma-separated path of the directory containing nvidia_drv.so and the
# default Xorg modules path
XorgModulePath=
XorgConfFile=/etc/bumblebee/xorg.conf.radeon