Ubuntu – How to switch between fglrx and ati drivers


How can I switch between fglrx and ati (open source) drivers without uninstalling fglrx?
The thing is I'm using FGLRX on a daily basis, because it's better for movies–OS driver displays annoying horizontal line while playing movies. FGLRX also does this, but it's less visible. That's only disadvantage of OS driver.

When I want to plug in external monitor with different resolution than my laptop's LCD I have to use open source driver, because FGLRX can't display two different resolutions at the same time.

I can uninstall FGLRX, but it's rather inconvenient to do this all the time. I've noticed that when I'm using FGLRX there is xorg.conf file and when I uninstall it, then the file is missing.

So my question is how to switch between them? It'll be perfect if I could do this without restarting my computer either.

I'm using Ubuntu 10.10, laptop/netbook MSI U250.

Best Answer

In theory it's possible: first, you should modify /etc/X11/xorg.conf, I think you need to modify things in the "Device" section (well, Xorg nowdays works fine without xorg.conf, as you noted too, so the other solution is rename xorg.conf so X won't use it).

But it's only the half part of the story, the other part is the kernel driver. I would "blacklist" fglrx as a kernel module, so it won't be load, when you don't need it: /etc/modprobe.d/blacklist.conf

I don't have a setup for ATI card in this way, but I have similar for nvidia, to switch between nvidia's binary driver and nouveau (open source driver for nvidia cards).