https://bugzilla.kernel.org/show_bug.cgi?id=117131 --- Comment #8 from Jason Vas Dias <jason.vas.dias@xxxxxxxxx> --- As stated on the web-page quoted above , ( https://wiki.archlinux.org/index.php/PRIME ) an example xorg.conf to use the discrete card as primary GPU is: # Discrete Card as Primary GPU Section "ServerLayout" Identifier "layout" Screen 0 "nouveau" Inactive "intel" EndSection Section "Device" Identifier "nouveau" Driver "nouveau" BusID "PCI:x:x:x" # Sample: "PCI:1:0:0" EndSection Section "Screen" Identifier "nouveau" Device "nouveau" EndSection Section "Device" Identifier "intel" Driver "intel" BusID "PCI:x:x:x" # Sample: "PCI:0:2:0" EndSection Section "Screen" Identifier "intel" Device "intel" EndSection My xorg.conf is basically the same with the string 'nouveau' replaced by 'ati' . It started out as simple as this, but then grew as I tried every conceivable method to specify the modes , but still the X-server exits with a 'No modes.' error in every case . The reason the X-server cannot determine the modes is because of this Linux bug - the radeon DRM driver makes incorrect ACPI calls. Also I think that if vga_switcheroo does not work or is incapable of working , as it provably is in the above example, it should return EIO on the write to the debugfs control 'switch' file , and not proceed to display spurious data in that file. -- You are receiving this mail because: You are watching the assignee of the bug. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
