I am looking to build a system with an AMD FX-8350 CPU, and a gpu setup that will last me three generations/years. I will always use a single 1080p projector, so no multi screens or higher resolutions need to be considered. Playing the latest games at max/near max settings and preferably maintaining 60 FPS, but never drop below 25 FPS
So wich one of these is the best:
*Assuming future generations of NVIDIA GPUs will be GTX 8XX, GTX 9XX, GTX 10XX, GTX 11XX etc...*
1) 2 GTX 760 SLI, then upgrade to 2 GTX 1060 SLI, then upgrade to 2 GTX 1360 SLI
2) a GTX 770, then upgrade to 2 GTX 770 when the GTX 10XX are around, then upgrade to a GTX 1370
3) a GTX 780, then upgrade to a GTX 1080, then upgrade to a GTX 1380
3rd option is what i would do, but 1st option gets you the most performance.
I always use single GPU's because i don't want to deal with the heat / power draw/ issues of a dual gpu setup. If you can live with that, go with the 1st option. I wouldn't buy an extra card 3 gen's later, don't even think that's possible (can you even buy a gtx460 now?)
When you get to the GTX1380 you will have upgraded the CPU and motherboard as well! Things go obsolete quick and you should think about what you need now. There is always something new around the corner that you must have.
Coming from a guy who's done it, SLI is not the way to go. Chances are by the time you want to add another card in, you won't be able to find the same one you have/ one that would work with your setup. SLI works best when you buy all the cards at the same time... I would trow my money into option 3, it will allow you room to change the other parts of your computer as needed and be much cheaper in the long run.
1080p is quickly becoming the new "low-res" in terms of high-end PC gaming.
If you only game at 1080p with a single monitor, I see no reason to go SLI.
1440p+ multi-monitor setup requires SLI, yours do not.
I have done the calculations regarding my distance from the 160inch projector screen, and found that any resolution beyond 1080p (also known as 2K resolution) wouldnt make a difference as there is a limit to our eyes ability to tell the difference.
future proofing is a fools game. there will always be better hardware available every year that will be better than whats available today. just buy what you'll need today and just change up when necessary (ie. when you are running below medium settings). you'll never run out of games that'll push your hardware to the limits but you'll run out of cash just to trying to chase that elusive "max settings" every time a new game comes. learn to make compromises and above all, be content with it.