It would be nice if you were more specific as to the exact usage. Is this mainly for gaming?
BTW, I'm not a big fan of multiple screens, the gaps between screens are pretty annoying when gaming. I personally have a Dell U2711 (27" 2560x1440). I absolutely love it for gaming. It's kind of expensive though.
Back to graphics cards:
GTX 275's for $200?
Some info on recommended cards:
1) GTX560Ti (about $230. recommend Asus or MSI version)
- supports Surround bet you need two. recommended if you decide on a single monitor
2) 2xGTX560 (roughly $330 for TWO cards)
- recommended if you want two monitors
- not NVidia obviously but I it supports at least two monitors in AMD's "Eyefinity" mode
4) AMD 7000 series (Q4 2011?)
- may use as little as 1/3rd the power of the 6000 series. No other details yet.
5) NVidia 600 series (Q2 2012?)
- will use as little as 1/3rd the power of the 500 series and FAR less power than any model before that.
If you are planning to play video games on two or three monitors and the obvious problem of the bezel between screens doesn't deter you, then your main problem is that you need to have sufficient Graphics Processing Power to do this or else you have to turn down the quality a lot.
Would you rather play on multiple monitors with low quality than on a single monitor with high quality?
Anyway, even a 2xGTX275 sucks for many new games and the technology is really outdated now.
- if on a budget, get a single monitor and at least a GTX560 graphics card
- if you decide on two monitors get a 2xGTX560 or 2xGTX560Ti setup
- if you decide on three monitors get a GTX560Ti or GTX570 setup
- I highly recommend waiting for the new NVidia's next year, or at least the AMD's (this year?) if the AMD's do what you want.
- if you want 3D you have to not only have supported monitors but your graphics cards must then be TWICE as powerful as your present setup. I wouldn't dream of setting up THREE MONITORS with 3D until the next NVidia cards come out.
Anyway, the setup you are suggesting would never support new games on multiple monitors at a satisfying quality.
I still recommend something more like a single 23", 1920x1080 monitor with a single GTX560Ti if buying now.