multiple graphic card

[gillekes]

Hello everybody,

It has been discussed before but I would like to start again. Wouldn't it be great to be able to use several graphic cards in the same mac. In theory we could go up to 24 outputs (4 cards + 8 THG). I'm saying this as some guys in Finland are showing up with something similar (http://www.picturall.com). Of course it is not as half as powerful as catalyst but it has 8 outputs right out the box and expandable to 24!

Richard: Do you think it is possible?

Thanks,

Gilles

[NevBull]

One of the main reasons that this is not possible is that you cannot synchronise the outputs across the video cards, so you could get different outputs displaying frames of the movie. At least with a Dual/Triple head, the signals are all from one output.

I am sure that if Richard could implement this, then he would

[gillekes]

Hi Nev,

But do you think this is related to mac os or to Catalyst. Those guys at picturall say all outputs are in sync.

thanks,

Gilles

[NevBull]

Correct me if I am wrong Richard, but I think its an OSX/hardware thing

[Mr_P]

Multiple outputs like the 'Picturall Octo' is possible from catalyst - to a limited extent - BUT only by using mix windows and a screen controller such as:
http://www.iiview.com/index.php/prod...all-controller

or multiple Matrox TH2G

(see thread http://chaldee1.gotadsl.co.uk/~richardb/upload/showthread.php?t=1698)


the reason you cant use more than one graphics card is that there is no internal apple hardware mechanism for transferring information like video images from one card to another without going through the pci bus or cpu. Also only low end graphics cards were ever supported with more than one card.

SO currently with Catalyst answer to multiple graphics cards is is no.

The 'Picturall Octo' server is an interesting system - it has an excellent output 'mapping'. It has custom MPEG 'type' enoding to achieve 4K resolutions. Its based on a linux system (although not mac). They claim 8 layers of 1920x1080 MPEG2 off a standard SATA drive and the outputs do appear to be in sync.

Do contact me if you require further info...

Simon

[gillekes]

These guys (http://www.sedna-services.com/download/videos/Presenter_Video_Wall_480p.mov) are using a mac pro with up to four graphic cards and their digital signage software to drive videwalls. They don't seem to have sync problems. I did not talk with them tough. So I'm not sure if their system is frame accurate...

[NevBull]

That system appears to run along the lines of Watchout - one server per area and, reading the info, only four layers.

It doesnt look to be along the 'live entertainment' lines that Catalyst is.

[Mr_P]

I had a quite in depth talk with the developer from Picturall...
(they were opposite our stand at PLASA)

The 'Octo' demonstrated was not a mac based system - although was Linux based. According to specs, it can run on MacOS, but I dont think theres a 'software only' version (yet?...)

System appears to be frame accurate - It has 32 layer capability - and apparently will playback 8 layers of HD MPEG2 footage. (1920x1880@30ps)
Its not a 'one per area' device - it has multiple outputs: 24 outputs per server (using 4 graphics cards and 4 x TH2G) - it can also be run in a network environment, control is va DMX / Artnet, and their own network interface
The control system isnt quite as cumbersome as 'watchout' - but is certainly up to 'live entertainment' sector and corporate or installation

re ~sedna
I wouldnt take their 'perfectly syncronised video wall' marketing claim as being technically accurate... The system is designed for advertising rather than the entertainment market

Do contact me if you require further info...

Simon