Built a new rig less then a month ago and due to some budget restraints @ the time I purchased a 1.25g evga gtx 570 hd superclocked over a 2g 670. Now being about a month later and having the extra cash I'm wondering what would be a better route for me to go. SLI my current 570 or take the card back (which is still within it's 30 day return policy) and grab a 670. I'm not overly impressed by the 570's performance as it is and believe it should, perform better then it does. I'm only on 1 Samsung 2420l Monitor 1920x1080 60 mhz, so the low memory of the 570 shouldn't effect me. I dont plan on running more then 1 monitor in the future, however I may want to upgrade to a higher reso one (which I'm sure the low mem of the 570 would be an issue) However this is not in my near future. I'm simply looking for better performance on my current set up. I only play Diablo 3 and WoW and have dropped to as low as 45 fps on diablo and 30 fps on wow in intense gameplay scenarios.
gtx 570 sli is all you need. It should perform bit better than the gtx 670. Although in games like battlefield 3, I noticed my gpu memory usage is sometimes as high as 1.8gb. Also the gtx 670 is cooler, quieter and draws a lot less power. Take whichever deal you find to be better and cheaper. Both gpu will suit your needs since you only play wow and diablo3.
The GTX 670 is the best card for it's price and performs better than the GTX 580 (even though you're talking about a GTX 570).
Tom's Hardware's article GeForce GTX 670 2 GB Review: Is It Already Time To Forget GTX 680?
Maybe this time will be different and we’ll see GeForce GTX 670s in sufficient quantity to satisfy the folks previously priced out of the ultra-high-end market. If that’s the case, then hell yes. GeForce GTX 670 is a phenomenal little board that blows right past the GeForce GTX 580—a card that was introduced at $500 a year and a half ago. It offers the display connectivity to contend with Eyefinity, one of AMD’s prior differentiators, and its efficiency is currently unmatched. We have every reason to recommend buying a GeForce GTX 670—even as an alternative to the GeForce GTX 680, which is marginally faster, but 25% more expensive.
Thnx guys. After doing some more research on my own and reading your replies, I took the 570 back today and got a 670. I was still within the 30 day return policy, so it only cost me $100 to upgrade. I almost forked over the extra $250 and got a 680, but just couldnt see spending the money for what I do on my rig. Installed it about 30 mins ago and am very pleased with the performance.