What should I do to increase performance in games such as Skyrim (w/ lots of mods) and future games? Should I do SLI or should I try to sell my GTX 670 and get something else? Perhaps wait for HD 8xxx to be released? Or should I just suck it up and be happy with what I have now? Just wanted some feedback from the community. I'd greatly appreciate it.
I'd always go for the best single GPU before I start thinking about SLI unless of course your talking about the difference between the 780 and the titan than it's different. I'd wait as your 670 can still handle all the latest games especially if your only playing at 1080p.
The GTX 670 is a more than capable card at the moment unless you're gaming at 2560 x 1440 or higher. Honestly, the best way IMO to keep yourself from falling behind is to buy a mid range card eacher year (660 Ti, 7950, that price range) and sell your previous card. It works better than trying to buy one or two enthusiast level cards like the 680 or 7970 and expecting them to last 3 years.
So my advice for you would be to keep that GTX 670 for now unless you really need an upgrade, and then get a Radeon 8950 or GTX 860 Ti when they come out, and then sell your GTX 670.
Thanks for the input guys. I'll think it over some more. I'll probably just wait for next gen; I don't particularly want to spend money on a GPU upgrade yet.