Which cards for 4 independent displays?

You guys are the experts, and I'm pretty out of touch with the latest technology. I need your thoughts/experience.

The main question is concerning the graphic cards to use. Any additional input will also be appreciated.

I'm building a desktop computer which will be monitoring financial markets throughout the day.
the monitors need to keep up with the data coming at them; that is, four 23" monitors at 1920x1080
I'm considering 512mb for each monitor, so that means 2 cards, with 1GB memory each

Planning on overclocking an i7-920 running on an asrock x58 extreme board (Reason for x58 board is I want a minimum of 2 pci-e 2.0x16 slots running at 16 lanes each so as to have max throughput to each card)

I've been told to stay away from the quaddro boards that drive 4 monitors - they just don't keep up well in this situation I'm told(surprised me).
I was encouraged to stay away from ATI and stick with Nvidia, because of problems with ATI not working well in this setup. However, I've been reading great comments and reviews on the ATI's, and they seem to offer more bang for the buck. However, I'm not married to either company, so I can go with either one's chipset.

My concern is, I just want to be sure that whichever cards I get, work well in a 4 monitor situation (wont be using SLI or Crossfire). I'd also like to keep cost reasonable - I don't need all the gaming bells and whistles, and I don't want to pay for more card then I need, but I don't want to be "penny wise and pound foolish." If an extra $30 will make a huge difference, well, let's spend the extra $30. Someone mentioned the Radeon 4870 as being at the sweet spot right now. Seems the 9800GX2, GTX260 is in the same class.


I'm considering this 4870:
http://www.newegg.com/Product/Prod [...] 6814121291


This setup needs to be rock solid, so I don't want a card that's temperamental.

Thanks very much for sharing your experience with me. I'm really impressed with the professional level comments and helpfulness in the forums. I realize this will not be a gaming pc, but perhaps some here have multi monitor setups like what I'm describing? Thx, as I'm really having a hard time deciding.