mergedFB with multiple radeon cards... also DMX/DRI

[Alex Deucher]

On Mon, 10 Jan 2005 22:39:25 +0000, Michael Pacey <michael at wd21.co.uk> wrote:
> Hi,
> 
> Is it possible to use mergedFB across multiple physical Radeon cards? I
> can get Xinerama working nicely but I want DRI to work too.

No.  Mergedfb only works on a single card.

> 
> My hardware is one 9200PRO AGP and two 7000/VE PCI cards. I want to keep
> my card->monitor all DVI-D (I get a better picture on my LCDs that way),
> which is why I'm not using mergedFB on the 9200PRO, which is a dual
> LCD+CRT card). The three cards have DVI-D outputs for my three LCD
> monitors.
> 
> One of my backup plans was to look into DMX (I have a second PC I can
> add add into this setup). However I was disappointed to see DMX is
> incompatible with the DRI. I interpret my web search results to mean
> that this is a limitation of the DMX architecture so I shouldn't hold my
> breathe waiting for this to be "fixed"; correct?

It's a problem with the DRI actually, the D specifically.  DMX uses
glxproxy to handle multiple backend 3d pipes.  It renders indirectly
to the backend X servers using GLX rather than directly to the
hardware (as is the case with direct rendering when you are on the
local machine).  So we need to get accelerated indirect rendering
working for DMX and glxproxy to work.  That is being worked on.  Once
that is working, you'd start 3 independant X servers with 3d accel and
then run DMX and glxproxy to get the desired 3 heads with 3D.  You'd
only really need one machine.

Alex

> 
> I suspect I'm asking too much on both fronts...
> 
> Thanks in advance for any advice!
> 
> --
> Michael Pacey
> 
> michael at wd21.co.uk
> http://sydb.dyndns.org
>