I have an HP Pavilion dv6 with switchable graphics: an integrated Intel GPU and a discrete ATI GPU (Radeon Mobility HD 6490M (1 GB DDR5)). Any attempt to use the ATI driver (either proprietary or open-source) fails because on reboot it tries to use the Intel graphics and so X fails to start up.
Normally there should be an option to disable the Switchable setting in the BIOS but HP have not allowed that set up.
Basically I'm stuck.
Thanks for your help!