I've done a bit of SLI research, and am still a little fuzzy. If I have two 550Ti cards using SLI, can I use 3 monitors?
Could I use 3 monitors if I disabled SLI???
The GTX 550 ti has a quite high pixel rate among the cards in that price range, that's why it does not lose that much performance when running in high resolutions or using multi-monitors, so you should be fine with GTX 550 ti SLI'ed..........but if i were you i would go for the single 560 since it will perform slightly better than 2 of the GTX 550 ti and cheaper