the i7-7700K does offer slightly better performance, i would recommend getting it because you might want to overclock in the future. If you can afford it of course. Playing some more intense games... a single 1080Ti maybe wont cut it. You'd get around 100-120FPS, if you got G-Sync or you arent as sensitive to stuttering, go ahead. I never benchmarked a 1080Ti, my number is based on math only, so i may be off.