well this is a curious one.

i've got my new gentoo, up and running, into gui... with the same xorg.conf as i had in toorox, but it keeps treating it as one screen, rather than three, as it should be, as it was in toorox.

so, same xorg.conf that gave me three screens, now gives one screen spanning three monitors...

it has all the screens, devices and monitors, as it should be, and as worked in toorox, but now in gentoo, when i load up nvidia-settings, at the bottom of the "X server Information" it says "Screens: 1 (Xinerama)", and in the side panel, there is, just "X screen 0"

the xorg.conf in question
http://paste.pocoo.org/show/455061/

i'm starting to wonder if it may be a randr issue? ... though i dont recall ever meddling with randr in toorox, maybe it was there, silently making my triple screen work as it should. i'm struggling to think why it's behaving like this... presumably some kernel config perhaps?

think it's time for me to switch to a xorg.conf.d configuration? and/or attempt a nouveau instead of nvidia?

sry, i'm getting rather exhasperated and fed up with this unfathomnable behaviour. HELP! X.|


edit:
Xorg.0.log
http://paste.pocoo.org/show/455080/
oh, might be some clues here. like the "EE" about glx

The log indicates the opengl interface (glx) is not loading, which is bad anyway.

Maybe:
1) delete your old xorg.conf
2) reinstall your NVIDIA drivers, allowing it to write the xorg.conf
3) make adjustments via nvidia-settings again to get properly display.

Also, are you using NVIDIA drivers from the Gentoo repository or installing them yourself? What version? Does the version match your card?

recompiled a load of stuff after sorting out useflags. thought it might be a simple case that xinerama support wasnt compiled into a number of relevent packages. ...same thing.

the GLX thing, i dont think is the issue, since xinerama deactivates it... they dont play nice together yet i dont think.

now trying your advice

as suspected, fails to load x server (failed to load modiules, no devices detected, no screens detected), so cant really get to step three from here. twas a worthy attempt tho.

drivers (from portage, using amd64 keyword) nvidia-drivers-270.41.19
card, dual 7800GTX

also
Server Version Number: 11.0
Server Vendor Version: 1.10.2 (11002000)
NV-CONTROL Version: 1.26
if that's of any use.

maybe i'm still missing some essential useflag or something like that somewhere, or worse, some kernel reconfiguration is needed. i'll keep looking.

(reboot did nothing to shift it either)


looking again in nvidia-settings...
there's still only "X screen 0" listed in the side pane, but in X server Display Configuration, all three screens show up, each numbered apropriately. 0, 1 and 2. ... so it's still as baffling as ever (to me at least) why they dont show up in the list on the left along with X screen 0. ~ and of course it still says, in the top option on the list ("X server Information"), "Screens 1 (Xinerama)"

the other weird thing, i didnt mention yet... it takes ages (like 10 seconds) to launch after typing startx. idk if that gives anyone any clues.

also... tint2 seems to understand there are three monitors (three screens), and appears on each, as expected. ...which is all the weirder consider nothing else does.

oh.

i'm in my old toorox install...and it seems it's doing the same thing of only showing "X screen 0" at the side.

of course, it seems to manage all three screens properly though. rather than just one, spanning all three monitors.

so this is the old stuff it worked with:
NVIDIA Driver Version: 256.53
Server Version Number: 11.0
Server Vendor Version: 1.9.2 (10902000)
NV-CONTROL version: 1.23

and looking in portage... i could probably try out 256.53.. to see if that works. :$

Newer drivers should be fine, since even 280 supports the 7 series.

I don't understand what you mean by a GLX / Xinerama conflict. AFAIK, they work fine together: (ftp://download.nvidia.com/XFree86/Li...hapter-14.html). My system loads GLX fine, and also uses Xinerama. What is the point of installing the accelerated NVIDIA drivers if you don't want openGL?

Humor me a bit: currently you are using 270 drivers from Portage. Download the latest 280 drivers from the NVIDIA web site and install them yourself manually. (You may want to remove the Portage drivers first.) Allow it to install the 32-bit compat libs (if you are running 64-bit gentoo) and allow it to create the xorg.conf.

Your xorg.conf is confusing. I don't think it is setup right. In the Layout section you tell it to use xinerama but in the Screen section you disable twinview. Which is expected since you are using xinerama, but you still configure it as if you were using twinview. But not correctly, with twinview there is only one Screen section which handles all monitors.

Here is what my Screen section looks like. I use twinview instead of xinerama.
If you want to use xinerama take out all the twinview stuff and in the Display Subsection add the mode line. Or if you want to use twinview set xinerama to 0 and setup the screen section like mine. You'll have to modify the metamodes line to include all 3 monitors and resolutions.


Or you could do what tinyTux said, which is simpler and probably better then my suggestion. Start nvidia-settings go to "X Server Display Configuration" setup the 3 monitors as you want them and tell it to save it.