2 graphic cards. What is used in system?


I have 2 graphics cards in system:

linux-urom:/home/alex # /sbin/lspci -nnk | grep VGA -A2
00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09)
Subsystem: Hewlett-Packard Company Device [103c:17f4]
Kernel driver in use: i915

01:00.0 VGA compatible controller [0300]: Advanced Micro Devices [AMD] nee ATI Thames [Radeon 7500M/7600M Series] [1002:6841]
Subsystem: Hewlett-Packard Company Device [103c:17f4]
Kernel driver in use: radeon

OS: OpenSUSE 12.3

I’m newbie in Linux.
How to determine what card is used in system? And how can I select the card which to use?


  • look in your xorg log (/var/log/Xorg.0.log)
  • it will be auto configured by X unless you manually configure it … in most likelihood, you are currently using the intel device
  • I would presume that this is a laptop … given that if it wasn’t, then the cable to the monitor coming out of the back system is attached to the graphics card, making it fairly easy to identify which device is driving the display
  • hybrid graphics in linux is currently not really user friendly … in particular, with AMD …

The yast2-hardware information might help you also.

Yes, It’s laptop HP ProBook 4740s.
I’m newbie and I can’t determine with /var/log/Xorg.0.log. It is unclear for me. Could you decode it for me? Thanks.

I can’t attach files. So that I placed it here: http://www.palmorder.com/files/xorg.txt

There I found information about my graphics cards. Unfortunately, no information which card is used.

Both radeon and intel drivers are loaded.

I note EDID monitoring configurations taking place with the Intel graphic driver.

    16.470] (II) intel(0): Printing probed modes for output LVDS1
    16.470] (II) intel(0): Modeline "1600x900"x60.2  107.80  1600 1648 1680 1930  900 903 909 928 -hsync -vsync (55.9 kHz eP)
    16.470] (II) intel(0): Modeline "1600x900"x40.1   71.87  1600 1648 1680 1930  900 903 909 928 -hsync -vsync (37.2 kHz e)
    16.470] (II) intel(0): Modeline "1024x768"x60.0   65.00  1024 1048 1184 1344  768 771 777 806 -hsync -vsync (48.4 kHz d)
    16.470] (II) intel(0): Modeline "800x600"x60.3   40.00  800 840 968 1056  600 601 605 628 +hsync +vsync (37.9 kHz d)
    16.470] (II) intel(0): Modeline "800x600"x56.2   36.00  800 824 896 1024  600 601 603 625 +hsync +vsync (35.2 kHz d)
    16.470] (II) intel(0): Modeline "640x480"x59.9   25.18  640 656 752 800  480 490 492 525 -hsync -vsync (31.5 kHz d)
    16.474] (II) intel(0): EDID for output VGA2
    16.478] (II) intel(0): EDID for output HDMI1
    16.502] (II) intel(0): EDID for output DP1

With the radeon graphic driver I note these errors:

    16.790] (WW) RADEON(G0): No outputs definitely connected, trying again...
    16.790] (II) RADEON(G0): Output VGA-0 disconnected
    16.790] (WW) RADEON(G0): Unable to find connected outputs - setting 1024x768 initial framebuffer
    16.790] (II) RADEON(G0): Using default gamma of (1.0, 1.0, 1.0) unless otherwise stated.

Based on that, if I had to bet, I would bet the Intel driver is in use in the system with the monitor device. ie the Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166]

I see, your lapttop is hp. If the radeon card came when you purchase it my
guess is, it is the one your laptop is using.

Find your laptop model in the hp support section and look at the specification it will
tell which graphic card was disabled.

Sorry I just look at your link, it looks like the intel is the one working.
The radeon could be the one to be used for the external monitor.

I know this may not be the solution you’re looking for, but I’ve never been able to get hybrid AMD graphics to work under Linux. I have an Intel HD4000 and an AMD 7670m. If you have a similar setup, you can view the status of your graphics cards with the command(as root)

cat /sys/kernel/debug/vgaswitcheroo/switch

It should print out both cards with an “off” or “pwr” by them and a “+” by the connected one. To turn the disconnected one off(Assuming it’s the AMD one), you can run (as root again)

echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

I know it’s not an ideal solution since it doesn’t make use of the more powerful graphics card, but if your laptop is getting hot, it might solve that issue while you sort the other one out. Also, if you reboot after doing that, both cards will default to being turned on again.

Good luck!

Thanks a lot for your answers.
Is there a way to select radeon graphic card for embedded monitor?

I solved the problem. Installed driver from here: SUSE/openSUSE - cchtml.com.