Dual Head semi-working, but not usable.

[pvtcupcakes]

I installed Fedora 13 with the fglrx (10.9) drivers, and after finding out the dual head configuration in the control center didn't work at all, I ran this command:

aticonfig --initial=dual-head --screen-layout=left --xinerama=on

After rebooting, I do actually have "dual screen", but the non-primary screen only displays black. I can move my mouse to it, and I can see my the cursor, but if I put a window there I can't see it.

I'm using fglrx 10.x from RPMFusion and kernel 2.6.34.7.
What kind of crazy bug is this.

[rohcQaH]

it's a bug in your desktop environment for failing to use the second screen

There are two ways for multiscreen support:

a) multiple separate X screens. Each screen can have it's own depth, vsync can work for each screen separately etc. Downside: you can't move windows between the screens.

b) a single X screen that spans multiple monitors. Dragging windows across monitors is simple, your desktop environment should be smart enough to use all available space etc.


aticonfig --initial=dual-head configures the first variant. To use the second, try configuring xorg.conf for a single-head config, then use xrandr to activate the second monitor.

[pvtcupcakes]

it's a bug in your desktop environment for failing to use the second screen

There are two ways for multiscreen support:

a) multiple separate X screens. Each screen can have it's own depth, vsync can work for each screen separately etc. Downside: you can't move windows between the screens.

b) a single X screen that spans multiple monitors. Dragging windows across monitors is simple, your desktop environment should be smart enough to use all available space etc.


aticonfig --initial=dual-head configures the first variant. To use the second, try configuring xorg.conf for a single-head config, then use xrandr to activate the second monitor.

I'm using XFCE. When I installed Fedora and it was using the open source drivers I did have working dual screen without any additional configuration, so I know XFCE is capable of it.

I could try out Gnome, but I still suspect fglrx is going to be a problem.

[rohcQaH]

No. The problem is that you've configured fglrx to use option a), while the OSS drivers default to option b). As said, configure fglrx to option b) and it'll work.

[pvtcupcakes]

I used aticonfig --initial and rebooted. And when I try to use xrandr like you suggested I get:

user@fedorabox ~]$ xrandr
Xlib:  extension "RANDR" missing on display ":0.0".
RandR extension missing

[rohcQaH]

I know it works for me. I suspect there's still something wrong with your xorg.conf. Can you pastebin it?

[adamk]

Sounds like xrandr was disabled via aticonfig at some point with:

aticonfig --set-pcs-str="DDX,EnableRandR12,FALSE"

Try to enable it with:

aticonfig --set-pcs-str="DDX,EnableRandR12,TRUE"

And then restart X.

Adam

[pvtcupcakes]

I know it works for me. I suspect there's still something wrong with your xorg.conf. Can you pastebin it?

http://pastebin.com/QeUQwV3K

[adamk]

You still have two screen sections. Remove /etc/X11/xorg.conf and rerun 'aticonfig --initial' because that's definitely not an initial xorg.conf file.

Adam

[pvtcupcakes]

Removed the old xorg.conf and reran aticonfig and xrandr works now.

[user@fedorabox ~]$ xrandr --output CRT1 --auto --left-of DFP1
xrandr: screen cannot be larger than 1680x1050 (desired size 2960x1050)

I tried adding a "Virtual 2960 1050" line to my xorg.conf but all that does is put my main screen at 1400x1050 (instead of 1680) with a max resolution of 1600x1600.