Single GPU vs SLI for multi-monitors


First off, I'd like to start off by saying I signed up on the site five minutes ago because I like the community and I need help.

Okay, so I've had my computer pieced together for awhile now. When I first built it I really had no idea what I was doing. Since tax returns came around I upgraded to a full tower case and an H100i instead of the stock cooler that came with my i5 2500k.

Anyway here's my problem. I run 2 monitors that are VGA connectors. I'm currently running a GTX 550 ti (I use VGA -> DVI adapters), and I'm looking to upgrade. My original plan was to go with 2x GTX 660's. My reasoning for this is because of the performance scaling against a single 670. I also don't want to go with another single card because the cards in the 600 series (as far as I know) only have one DVI-A port, and VGA can't be converted to DVI-D, so if I was using a single card one of my monitors would be useless. But if I were to get a single GTX 660 ti, and buy 2 new monitors, and upgrade my card every year or so, would that be money better spent? Because I know of SLI configurations having driver issues and such.

Sorry for my thoughts being all over the place. Any help is appreciated :)

Im running with 2x 660 system right now, upgraded about 3 months ago, and there have been minor stutters in the game, for about half a second once during an hour or so, but havent really ran into any major problems.

Single card solution is usually considered more stable, but if you want to do Surround (3 monitors) and still run everything on ultra, its either a 680+ card or SLI / Crossfire. 

Now 660 SLI will propably serve you fine for about 3-5 years, because performance wize, its slightly faster than 680.

However, since the 7 series is coming out, im expecting the prices to drop. So you can even go more high end if need be.


*As for connectors, dont use vga... 

Also adapters are a bad idea when it comes to gaming. 

Hooking 3 monitors up to a single card is not really a problem, because most the new stuff is compatible with different types of connectors, i did DVI to HDMI and hooked up 3 monitors, + 1 HDMI with 660, you can find both DVI - I and DVI - D cables / crossovers. 

I can give you more info on how to hook the different connectors up, but nvidia manual covers most of it, and you should get help from there.