Does it exist? I know there are a couple full-height. I have a machine with only one full-length PCIe slot that's low profile only. I don't think it exists.
I don't think so either. Only cards I recall with >4 ports are Eyefinity 6-port and Eyefinity 12-port. Can you run the rig with the case cover off to accommodate a full-height card?
I currently run two FirePro 2460 cards, each is capable of supporting 4 monitors, so eight total. They use mini-display port connections, I don't do any gaming or graphic intensive work, so they are fine and well priced.
It's for a client so it's got to be somewhat non-ghetto. I will try a riser cable and see if there is room in the box, it's really small, a gateway SX 2855. I think I may limit it to a quad card... Not ideal but we'll see... There are Dell and HP options that work but they are more $$ This could be the first of many. If I can make it happen in the budget they may want 50 machines.
With a maximum 220 W power supply I'm not even sure a 4-port card will work for you. Even this card requires a 400 W power supply, although the reviewer on Newegg claims it works on his system with a 240 W PS. It has 4 mini DP connectors. Its not a very fast card however of course its only $140. There's also a 4 DVI card which is about the same in quality. I did find a half-height card that might work for you. Its the AMD FirePro W600 but its about $500. It has 6 mini DP connectors
Worlds Smallest, Hot and Fresh, may need to bump out the case tho . . . http://www.gizmag.com/worlds-smallest-supercharged-four-stroke-v8-production-engine/24372/
Maybe you should buy new computer... or you can try something like this if you have at least one USB 3.0: https://www.youtube.com/watch?v=pYUdAWOGJ_Y
With time hopefully 2 of these monitors will suffice: http://www.lg.com/us/monitors/lg-34UM95-P-ultrawide-monitor
Thanks for the input everyone - I've found an alternate solution - it's not ideal however I think it's all that will work. It's smaller and "better" in some ways - but blows the budget out of the water AND has no warranty... This is what I was thinking about trying... Some of the new Dell and HP machines have dual-Display Ports on the motherboard as well as one VGA. There are BIOS settings supposedly allow you to use the onboard graphics in addition to the onboard video card which gives you a total of 2 onboard + 4 add-on with a video card. I found someone who had an Optiplex 7010 SFF and we tested it out with an Nvidia NVS 420 card - and it didn't work exactly as I wanted AND it was the Small-Form-Factor size, not the USFF that I was going for. After some time on NewEgg I found a great Gigabyte brand motherboard that's got a DVI AND two HDMI ports on the motherboard: (http://www.newegg.com/Product/Product.aspx?Item=N82E16813128721) and it has a full-size PCI-e x16 3.0 expansion slot (needs a proper chassis and a 90 degree adapter but it "should" work). I didn't want a home-brew solution because of lack of warranty, time to build, etc. but this is going to potentially support up to 7 monitors (4x from PCIe add-in card and 2x HDMI + 1x DVI). It's also able to support 16GB of memory, has onboard WiFi, 6x SATA ports and accepts an i7 CPU. This particular office is currently setup with about 10-12 5x monitor setups (two up top and three on the bottom) so I didn't NEED 6 monitors, just 5 but having the option for 6 is nice. The only issue is this will blow the budget out of the water... It's going to be easily a $1000-$1,500 setup vs. the ideal price of $500-$700 I was going for.