I've been meaning to share my thoughts on this cpu for a while since a few people have mentioned sharing during race chat. (not a brag)
First up, this upgrade from 6700k was probably not needed and is an expensive one considering the small gains to be had...but I had the itch like some others here. With the 6700k I was noticing some hitching/micro stutter in AC particularly when the leader crosses the start/finish on the first & last lap, also when people were entering discord chat during practice. I was unable to find a solution/optimisation, the cpu was already overclocked to the max and the (small I know) issues being just annoying enough to fuel my upgrade itch. I believe the 8700k has helped a lot but not totally rid the issue, doesn't happen with discord any longer, but still very occasional (much smaller and less frequent) micro stutter in ac start/finish line. So the extra cpu threads/resources have helped my system overall, particularly when running multiple background tasks eg, Sim Hub, Crew Chief, discord and what ever else windows tries to do these days. Battlefield 1 frame rate has increased by a nice margin, previously was about 90-125 fps with my settings and now at 110-150 fps, the only thing is it's not perceivable, the game ran so smooth anyways.
So if your thinking about upgrading, the price to performance is not great but the performance is there especially if your on older hardware.
These 14nm cpu's run hot so I've done the de-lid and apply liquid metal on both my cpu's but the 6700k had custom water cooling and the 8700k I have a big Cryorig R1 Universal air cooler and temps are quite nice.
My 8700k seems to be a decent one, not golden but not shite, settings;
5Ghz @ 1.3v, vcore in hwinfo reads 1.32v under light loads and 1.29v under heavy load/stress tests, so still a small amount of vdroop.
Cache is set to stock, no overclock there.
Ram is 4x 8gb 3200 @ 3466mhz with vccio @ 1.15v and vccsa (internal memory controller) 1.18v. Hwinfo shows these at 1.17 & 1.19 respectively. Also xmp profiles usually pump too much voltage into these, upwards of 1.3v unnecessarily increasing cpu temps.
All other intel turbo, speed step, power saving features are still enabled. I haven't the cpu any higher yet, very happy with where it is now.
Just sharing my results for those interested and for the guys that have the same cpu. Any questions I'll try my best to answer, I'm not a pro at this stuff just a pc/gaming enthusiast, it's my hobby I spend my hard earned on instead of beer or whatever (don't you judge me lol).
I'm also interested in the guys sharing there thoughts on the ryzen stuff since I almost converted to save a few bucks but only stuck with intel because I'm familiar with it and I knew my ram was compatible.