So I know one of the advantages ATI has over Nvidia is the Eyefiniti support, which treats 3 (or up to 6 monitors) as one, and that Nvidia can't do that.. Does this mean Nvidia doesn't have multiple monitor support (or that it's limited to only two), or does it mean that Nvidia can also have 6 monitors but I just doesn't treat them as one?
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In Fact, Nvidia does support 3 monitors as one but it requires an SLI setup to do so.
To answer your other question, if you have two GTX 285's with two DVI outputs each, you can use 4 monitors...