Powerwall design

[Rachie5272]

I've been promised a bunch of free LCD monitors, so I'd like to build a powerwall with them.  I only have two on hand so far (19" Dells with VGA, DVI, and USB hubs), but chances are the others will match fairly closely.  I'm trying to figure out how to best connect these things together.  I'm considering either a 3*3, or 4*2 grid.

So far I see two major routes.  The first is to get a couple fancy graphics cards which can handle several monitors each, and stick them in a single motherboard.  This is probably the easiest way, but I know next to nothing about modern video cards.  I haven't followed them since the days of AGP.  I abhor windows, so they need to have Linux support.

The other route is to get a bunch of Raspberry Pies, and network them together.  This has the major benefit of scalability.  I don't know exactly how many monitors I'll get, but this way I can always add more.  I can get power from the USB hubs.  There's also a Pi library for playing video this way.

As for what to do with the thing once it's built, I was thinking of displaying stretched video, playing Doom (a must for any new hardware configuration), and possibly google maps/earth.  This should be very easy on a multi video card setup, but configuring the Pies will be harder.

Does anyone have ideas or suggestions on what to do?  My budget is $500, but I can probably bump it up to $1000 if needed.

[mianchen]

Wouldn't a $1000 projector be a better and simpler solution?

[Rachie5272]

If you can find a projector which can do better than 1960*1080 for under $1000, then sure.  The point of a powerwall is resolution.  I admit video will become a blur unless I 3D render something in full resolution, but the other applications utilize the extra pixels.

[homebrew]

Nice you get the LCDs for free ... now you have to pay for the graphic cards ...

Cards with more than two high resolution outputs tend to be (very) expensive.

However there are mainboards available with lots of PCI-E slots.
This one for example (just an example!!!) features 5 slots: http://www.gigabyte.com/products/product-page.aspx?pid=3891#ov

Here is an example of a 2xDVI card that should fit in a single slot:
http://www3.pny.com/NVIDIA-NVS-300-x16-for-Dual-DVI-or-Dual-VGA-Low-Profile--P2951C364.aspx

So yes, such a system seams to be feasible for less then 2000 USD and would be capable of driving 10 FullHD-Screens while being linux compatible.

Pete

[mianchen]

http://www3.pny.com/NVIDIA-NVS-300-x16-for-Dual-DVI-or-Dual-VGA-Low-Profile--P2951C364.aspx

These can be had for very cheap from *Bay. I bought a NIB HP one for less than £10

[Rerouter]

If you do not care too much on GPU rendering you can generally enable the on-board GPU outputs on a motherboard, with anything built in the past 4 years supporting 2, then you grab a last generation gaming card, that will get you an extra 3 (possibly up to 5) which gets you to 5 (or 7) and another to get you to 8 (or 12),

you would avoid all the multi-gpu stuff like crossfire or SLI, have the gaming card as your main gpu (windows will render everything on the 1 gpu) and off you go, in general intel drivers will not fight nvidia / ati drivers and on my own setup i can attest to that, (on die gpu from I7 3770 cpu (2 ports) , with a HD5850 as my main card (3 ports), and a X1950 which is a carry over from before i upgraded the motherboard, (2 ports)

all these are currently living happily on the one computer,

[Psi]

You could do 3x3 with one dual DVI videocard and two Tripplehead2Go converters.
http://www.matrox.com/graphics/en/products/gxm/th2go/digital/

The matrox tripplehead2go boxes convert multiple monitors into one huge monitor for the videocard.

So with 3x 1920x1080 lcds it presents one 5760x1080 monitor to the videocard/OS.
Therefor using two dvi ports and two matrox boxes you can have 2x  5760x1080 (one above the other)


I've heard that there's a few catches though, im not sure all videocards can accept 5760x1070 etc..
Also, it doesnt support 1920x1200  (only 1920x1080 or lower)
So it would pay to do research before choosing this option.