Nope, a crappy 10-20 FPS, 2GB won't cut it, and 760 is not what you should have to play on 4k. 760 is not comfortable with all settings maxed out even on FHD, it won't manage more than 25-30 FPS on low-medium settings on 4k.
It will not run a 4k monitor but if you wait a certain time for the new GPU line up to NVidia and their said they will probably drop fast in price. I would say try to pick that up and it would run smoother. Other option is to buy one extra 760 and take it as SLI - that means double the VRAM and would probably run some games depending on the resolution on 4k. Hope that helped little
I know, 4k gaming is an immature technology as of now. My 290 Tri X doesn't manage anything better than 30-40 FPS on most games on high-ultra on my 4k. But my build isn't a gaming centric rig so that's fine. AMD tend to run hot, and even the best air cooling will be short for 290X's 3/4 way crossfire. Water cooling will add $$$ to the build. I hope 900 series brings us some better 4k performers