What I would like to be able to do:
I would like to be able to switch between my dedicated graphics card (AMD) and integrated chip (Intel) from the BIOS, that means:
Restart → BIOS: set to integrated Intel enabled (only) → boot
or
Restart → BIOS: set to discrete AMD enabled (only) → boot
This type of primitive switching works fine when running on open source drivers. However, as soon as I install fglrx
, switching from AMD to Intel from the BIOS breaks the session and the system falls back to low-graphics mode on boot-up.
What I did:
- fresh system, open source drivers with Intel enabled
- switched to AMD = no problemo!
- switched to Intel = no problemo!
- (the above repeated few times and tested for performance issues)
- installed proprietary AMD drivers per http://www.unixmen.com/ubuntu-12-10-and-amd-catalyst-problem-solved/ (PPA) ⇒ working fine after restart!
- switched to Intel ⇒ broken configuration, i.e. system boots to 2D/fallback mode!
Why do I need it?
First of all, it's a matter of my curiosity. More importantly though, getting this thing to switch on AMD proprietary would be huge for me.
I was asking about AMD/Intel switching a while ago and while I got the answer, 1) it doesn't work 2) I can't contact the author of the answer 3) I suspect the answer is overcomplicated.
In summary I need help either with this question or with the old one linked above.
System information:
Ubuntu 12.04 amd64, installed clean
Lenovo Thinkpad T500
Intel GMA 4500MHD / ATI Mobility Radeon HD 3650
I haven't tried this with an AMD adapter, but your issue is common to integrated vs. discrete Nvidia graphics setups as well (tested on a Lenovo Thinkpad T510s).
Under normal circumstances, an open source graphics driver is automatically selected by the X server during boot based upon your adapter selection in BIOS -- integrated vs. discrete.
When enabling proprietary drivers while the discrete adapter is in use, an Xorg configuration file is created in
/etc/X11/xorg.conf
in order to explicitly tell the X server to use the proprietary driver. While this configuration file exists, X will use the driver specified in it rather than auto-detecting your hardware setup. You can see how this would be problematic when you switch back to your integrated graphics adapter; the AMD/Nvidia proprietary driver is still specified in thexorg.conf
file.The way to safely revert back to your integrated graphics adapter is to delete the
xorg.conf
file:Alternately, you may rename the file such that it can no longer be found by X:
On your next boot, when no
xorg.conf
file is detected, the X system will again auto-detect your hardware configuration and load the appropriate open source driver.Currently there is no solution for this problem. You can read more about it here: http://phoronix.com/forums/showthread.php?78813-Simple-graphics-switching-through-BIOS/ I'll ask moderators to re-open the question when a viable solution comes into light.