As stated in the topic, I have the following problem: there're two VGAs in my Lenovo G770 laptop with Ubuntu 11.04, namely Intel Mobile HD and AMD Radeon HD 6650M. And if integrated videocard is working quite fine, the discrete one doesn't work at all. What I try to do, is to make the ati card work, no matter if it will be switchable graphics, or just ati working at its full potential.

I tried proprietary drivers: fglrx, compiling ati's drivers in various ways; standard ubuntu driver. There's no option in BIOS to turn just discrete adapter on, so I got to stick to "switchable". ATI Catalyst does not allow me to switch video adapters while integrated one is active.

Furthest I got myself is working vgaswitcheroo module. But here are some problems too. First of all, it does not respond to echo DIS command, but does turn the card off with echo OFF. I figured that all I have to do is echo DDIS to make delayed switch, and reboot X server to make use of ati adapter. What happens then is black screen, sometimes some of console booting lines are visible; although login screen is loading, but not visible (I can tell by sounds and by shortcuts working, so I can login in blind way). I guess this means that ati card is finally working, but something is wrong with it.

Because of the "black screen" glitch I cannot really even check what card is working.


Given your progress on finding vga_switcheroo I'd be tempted to reinstall the OS, (and update to the latest version of Ubuntu) just to be sure that your original attempts to change drivers didn't actually set you back and break the drivers for your discrete graphics card.

My guess is that the drivers were originally fine, but that you originally needed to issue requests to vga_switcheroo to restart your session (logging out should be enough if you want to avoid an actual restart).

It's interesting to note that the choice of graphics card which is powered up originally may depend on whether your laptop is plugged in or not (depends on manufacturer, I don't know if this is the case with you). Perhaps that's what they mean by switchable mode in the BIOS.

https://help.ubuntu.com/community/HybridGraphics suggests the following as you mentioned, but worth looking at the entire page to verify what's right for your case.

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

Generally speaking you're best off with hardware support from the most recent linux kernel you can get, which means that you may get better results from installing Ubuntu Oneiric Ocelot (11.10) than with Natty Narwhal (11.04), which will mean a more up to date set of software all round.

If you really want to push things forward, adding the X-swat repository will give you more bleeding edge versions of your X server (the software which provides the windowing environment for Ubuntu).


If you're totally crazy, it's possible to use the Xorg Edgers repository, but the warnings about it are real, and if you use this on a system you care about, you have to be very comfortable on the command line and with apt pinning to reverse any changes which break your build.

Caveat: Although I'm an experienced linux user and administrator, I'm just learning about switchable graphics as I'm anticipating delivery of a dual-card Dell Q15R with Intel HD 3000 and GT 525M (Xmas present to my self). I'll be testing this out for myself pretty soon.

  • Thanks you for the answer! Considering BIOS options: no matter, plugged or not, computer boots with integrated card on. At least Ubuntu does. I'm not really comfortable with 11.10. so I'll keep this variant as last resort. And Xorg Edgers are not for me either, as I am quite a rookie in such things. I guess, I'll try reinstalling ubuntu and trying to get vgaswitcheroo to work without messing up the drivers. Thanks again for the answer. – cotique Dec 28 '11 at 12:24
  • Finally, I decided to go for 11.10. Is it okay if I'll just update my 11.4? Or it needs to be a complete reinstall? – cotique Dec 30 '11 at 16:32
  • It's really tempting to go for a complete reinstall, as it implies there's nothing left over from my previous attempts to reconfigure things, especially because some recent install wizard behaviour attempts to maintain some of your installed packages too. At least that's my choice, but many people will update and have good results. 11.10's supported until the same data as the last Ubuntu LTS (long term support) version so you may as well choose that before going for 12.04 LTS when it's out. – Cefn Hoile Jan 9 '12 at 11:56
  • I reinstalled Ubuntu and I have the same problems with new version. So it goes. – cotique Jan 30 '12 at 0:17

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