On the back of the GTX there's 2x DVI & 1X Mini HDMI output, could I run all three simultaneously, and connect each to a monitor?
Or should I buy two lesser cards, and run them out of SLI to give me 3 DVI slots?
Please give me a suggestion for the mobo / gfx card(s) pair.
Nvidia cards can't use three monitors on a single card. You need an AMD card for that. I'd return the the GTX470 and get a 5850 if you need gaming power. If you aren't playing games and just want a big desktop to watch stuff on, the 5570 or better will be fine. I think I read something somewhere that said the 5670 is needed to run some high end HTPC setups. (bit streaming and things like that.) If your just watching videos and using computer speakers the 5570 will be fine.