Arch Linux

rxvtk

Member

Registered: 2013-10-15

Posts: 24

lspci detects second monitor on different gpu, but xrandr does not

Monitor 1: DVI, using ati driver
Monitor 2: VGA, using intel on board graphics

When I set Monitor 1 as main monitor in bios, lspci does NOT see other monitor, nor does xrandr.
When I set monitor 2 as main monitor in bios, lspci DOES see the other monitor, but xrandr does not.

I followed https://wiki.archlinux.org/index.php/Xo … e_monitors
and set

Section "Device"
    Identifier             "Screen0"
    Driver                 "xf86-video-ati"
    BusID                  "PCI:2:0:0"
EndSection

Section "Device"
    Identifier             "Screen1"
    Driver                 "xf86-video-intel"
    BusID                  "PCI:0:2:0"
EndSection

However, if I try to reload x, It just says no screens found.

How can I get dual monitors when using two different gpus/drivers when xrandr doesn't even see the other monitor

emeres

Member

Registered: 2013-10-08

Posts: 1,570

Re: lspci detects second monitor on different gpu, but xrandr does not

You need to define 2 devices, 2 screens and 2 monitors. And use other identifiers, devices for devices instead of screens. That is just confusing. After that you may need to add the display switch or variable for xrandr. Look at the last post here.

skottish

Forum Fellow

From: Here

Registered: 2006-06-16

Posts: 7,942

Re: lspci detects second monitor on different gpu, but xrandr does not

Change your drivers to the driver's name and not the package name as well: intel and radeon.

Last edited by skottish (2014-06-15 00:40:58)