Triple-head and Xinerama status (or lack thereof?)

[Alex Deucher]

On Wed, Apr 18, 2012 at 11:49 AM, Fernando Cassia <fcassia at gmail.com> wrote:
> Hi there,
>
> I´m new to this list (but not to Linux, started with Caldera OpenLinux
> at the time of Xfree86 and 2.x kernels) so please bear with me.
>
> My current setup includes an AMD Opteron server-workstation with one
> PCI-X ATI X1600 board, which its dual DVI+VGA outputs. That card has
> two 19' monitors connected, a DVI one and a VGA-only one, both LGs
> (FWIW). I run the latest greatest Fedora (F17 Beta) with Xorg 1.12.0.
>
> Now, for budget reasons suppose I don't want to buy another gfx board,
> but rather connect an external USB-to-VGA framebuffer adapters like
> these:
> http://goo.gl/TqchG
>
> Would current Xorg recognize the 3rd display (no matter it being much
> slower due to the USB 2.0 interface) and put the 3rd screen alongside
> the other two so I can move app windows from one monitor to the next,
> just as the latest Xorg along with FOSS ATI drivers did with the two
> current displays?
>
> Or would it be a separate X display because it's handled by a different driver?
>
> I have asked on the Fedora list and the answer hasn´t been encouraging.

Assuming there is a driver for the usb device you want to use, it
should work fine barring the xorg.conf changes needed for xinerama.
Also note that with xinerama enabled you don't get hw accelerated 3D
support.

Alex