Yes you can add a 670 at any time and performance should be enough, though that motherboard will have no expansion slots left if you do SLI.

 

if you think you are going to go 3 screens, get an equivalent ati card, (single) nvidia cards are only good for 1 or 2 screens.

 

You'd be wrong, the 600-series graphics cards from Nvidia allow up to 4 screens.

 

Doesn't mean they're good at it. Nvidia's Surround technology is software based rather than hardware. ATI Eyefinity, for all its bugs, is still more efficient.

Also, Arma III is looking amazing, so I reckon you'll need at least a 670 to run it on full settings. 670 is also good choice if you want the potential upgrade path to two 670s in SLI.

 

If you think you might need expansion cards for anything (wireless, additional USB ports, firewire, whatever), then the AsRock board I suggested would be the better choice. With the ASUS board, you only have three expansion slots, and the third will be covered by your second graphics card if you do SLI in the future. The AsRock will still have a few open. Also, AsRock was formerly ASUS's budget brand, which has since spun off into making its own high-end boards, so they're still sorta ASUS...

Regarding graphics cards, two 670s should be more than enough to run three screens, though Kai and Beonid are right - AMD Eyefinity is the superior multi-monitor solution. Doesn't mean that NVidia Surround is useless or unworkable though, and the NVidia cards are superior to the AMD cards for less money.

 

Ok, let us switch the motherboard to http://www.newegg.com/Product/Product.aspx?Item=N82E16813157295

If I were to go for AMD/ATI, which card would be equivalent to the 670?

 

The 7970. It'll be about $30-$70 more, depending on which one you get.

 

Which one would you suggest? Money's not really a problem right now.

Same as above. If I decide to stick with 670, which one is good?

Also, I am thinking of posting the final rig I decide on on some hardware forum(s), since I will be getting parts from half-way around the world I don't want to get something bad/incompatible. Any suggestions (on the forums)?

 

The 670 beats the 7970 at lower resolutions (up to 1080p), but gets edged out past that. If you know for certain that you'll be gaming on multiple monitors before the time comes to upgrade your graphics, then the 7970 is the way to go. It's got more VRAM (3 GB vs 2 GB on the 670), and Eyefinity is superior to NVidia Surround.

I used to be pretty active on the Toms Hardware forums, and they're pretty good for getting advice. Just follow the directions in the first sticky.

 

I just built a new gaming rig with the gigabyte windforce 670 oc and all I can say is you can't go wrong with it. It's extremely quiet (atleast to me) and runs all the games I play on the highest setting. Well worth the money spent!