6800k vs 7700k in the future

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Actually Coffee lake which is supposed to be a 6 core CPU is coming next year and it will be a mainstream CPU. I don't expect games to start requiring more threads as a result though. Though it will be a mainstream CPU it will be on the high end of that spectrum. Really I consider 6 core CPU's as more mainstream today. The 6800K is affordable for a lot of people including you and in my eyes that makes it sort of mainstream even though it's for Intel's high end platform X99. I consider the high end platform behind a bit though. Right now X99 is only on broadwell which is technology from 2014 but the extra cores do make up for the small percentage of extra single core performance you will find of the Kaby Lake Core i7 7700K. Kaby lake is...
They cam handle pretty much everything as long you pare them with a good gpu. If you have a budget then go cheaper but mostly up to you. The 6800k won't be better than the 7700k but could be better worth for you money.
 
It's going to be a looooooong time until more then 4 threads becomes standard. When 4 thread became somewhat minimum, it annoyed a few people with old dual cores that had no hyperthreading, but if 6+ core became minimum, it would completely screw with everyone who runs an i3 or i5. Don't worry about needing more then 4 threads. It won't happen until 6+ threads becomes mainstream, and thats far down the road.
 


 
Actually Coffee lake which is supposed to be a 6 core CPU is coming next year and it will be a mainstream CPU. I don't expect games to start requiring more threads as a result though. Though it will be a mainstream CPU it will be on the high end of that spectrum. Really I consider 6 core CPU's as more mainstream today. The 6800K is affordable for a lot of people including you and in my eyes that makes it sort of mainstream even though it's for Intel's high end platform X99. I consider the high end platform behind a bit though. Right now X99 is only on broadwell which is technology from 2014 but the extra cores do make up for the small percentage of extra single core performance you will find of the Kaby Lake Core i7 7700K. Kaby lake is a strong CPU with very good overclocking capabilities. It seems very possible to reach 5GHz on the Core i7 7700K while the 6800K might not comfortably go beyond 4.2GHz. So that's a very good single core advantage on the Core i7 7700K and for gaming that's what you want. Another thing to note is if you want to watch Netflix in 4K on your computer right now a Kaby Lake CPU is the only way to do it. I'd go with the Kaby Lake Core i7 7700K because it's slightly newer technology, it's faster for gaming, and you can use it to watch Netflix in 4K. If you have a 4K display. If you were doing lots of video editing and such I'd say the 6800K would be a little bit better option but you didn't mention anything but gaming. As far as the future goes nobody knows but I'll say this... At the rate that CPU performance has been improving I expect that the Core i7 7700K will last 5 years for gaming or possibly longer. The Sandy Bridge CPU's are still viable for gaming today and those are now 6 years old. The Core i7 2600K is still an awesome gaming CPU, the 3770K is also a very good option too and those are for people who can't afford to buy new.
 
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CPUs have indeed barely improved over the last 6 years, although AMD might force Intel to start investing some in R&D. For example, my 3570k outperforms the average overclocked i5-6600k, even though it's over 4 years old.