I have some spare cash to spend. My current PC is X99 + i7 6900k (no OC) + single 1080 Ti FE (purchased at launch). This has been the best video card I've ever bought (still powerful enough for most games after 2 years, hold value very well - thanks, RTX) If I'm to sell it, I'd have to dump another $700 to get the 2080 Ti... and only get about 30% performance increase. However, if I get another 1080 Ti for $500-550, in some games (Shadow of the TR...), I'll get ~ 90 to 100% performance boost. Any recommendations? And it looks like we're not going to see any "performance breakthrough" from either nVIDIA/AMD anytime soon. /TL,DR: - Have some cash & upgrade itch, play games at 4k. - PC: X99 + i7 6900k (not OC) + 32GB DDR4 2400 + 850W PSU (should be enough for 2 x 1080 Ti). - Adding a 1080 Ti for ~ 550 bucks (~ 90 to 100% perf. increase in Shadow of the TR...) or selling 1080 Ti and add $700 for a 2080 Ti (30% perf increase)?