USAGE FROM MOST TO LEAST IMPORTANT: I will mostly be just wanting three or four screen support, and capability to play modern games at a decent FPS. I do use Photoshop, GIMP, sometimes 3D modeling software, so I think I might need a lot of memory on the GPU?
CURRENT GPU AND POWER SUPPLY: Corsair HX650
OTHER RELEVANT SYSTEM SPECS: CPU: i7-3770K; Mobo: Gigabyte GA-Z77X-UP5 TH; 16GB RAM
PREFERRED WEBSITE(S) FOR PARTS: newegg.com, amazon.com
COUNTRY OF ORIGIN: United States
PARTS PREFERENCES: any that are good...
SLI OR CROSSFIRE: Yes
MONITOR RESOLUTION: 1600x900 HD, although I am in the market for new monitors, any recommendations for under $200 each?
ADDITIONAL COMMENTS: None really, could you explain why a particular card you recommend? I don't know much about GPUs, so I am trying to learn.
For 3d modling, I've heard the more Vram the better, but I'm actually unsure about this statement, I'm sure it's true, but either card would do good for Gaming, but the 660 is better for what you want to do.
I do know a bit about GPU's have been researching them pretty extensively over the past few month... but usually the higher end models. For $200 you can get either a Radeon 7850 or a GTX 560 Ti. The Radeon WILL outperform the 560 Ti Slightly, not by much. Also, AMD usually does a really good job for Multi monitor setups. Therefore if you intend to use more than one monitor Radeon 7850 WILL perform better. However, you say you want to CF, which means you will be spending $400. I would recommend spending that on a single GTX670 or a Radeon 7970. Right now Newegg has a GTX 670 FTW for $419.99 (which you can overclock fairly substantially) which would outperform CF 7850's and use a LOT less power.
Also forgot to mention.... CF 2 7850's with your current specs, your PSU load will be very very close to max. SLI 2 560 Ti and you will hit over 700W. You have a good PSU, bbut low Power availability. So you should be good with 2 7850's but if you intend to OC anything you will likely experience many crashes and BSOD's. Best to go single more powerful card or up your PSU before you CF/SLI.