Also note what it shows in that manual are 8,6, and 4 core and I would assume they are talking about the 6-core/12 thread, and 4 core- 8 thread. More threads means not going to overclock as well because of voltage, and the heat it will produce. But a 6 core with a easy overclock to 4.0 with one dial turn is going to be nice.
That's not necessarily true since the chips are binned.
The 6-core chips are essentially failed 8-cores with two disabled - which is likely a factor in why they are not shipping right away.
The quad-cores have one CCX instead of two, but heat is usually not the limiting factor for 'sensible' overclocks these days.
There's a limit to how much voltage you can use safely if you expect to keep that CPU for a long time.
I could probably have pushed my 2500K to 5GHz if I decided to exceed Intel's recommended maximum voltage, but it's unlikely that I would still be using it six years later if I had done that. Instead, this CPU is only stable up to 4.5GHz.
Temperature was not an issue. It never exceeds 60C under full load, so additional cooling wouldn't make a difference.
The only way that I'd be able to push the clockspeed higher would be to increase the voltage beyond safe limits.
Now we don't know what the situation is with Ryzen, but I see nothing to suggest that the lower core chips are going to overclock to higher speeds, or that you'll be able to push them to something like 4.5GHz on all cores with safe voltages.
It would be great if you could though.
Do CPUs like the the dual-core i3-7350K overclock much better than a quad-core i7-7700K?
I honestly don't know the answer to that, but I would be surprised if they did.
Intel and those insane markups. They're the Apple of CPUs.
You should see how much Apple marks up Intel CPUs based on their list price.
Apple were charging something like $1000 more than Intel's list price to upgrade to the fastest CPU in the Mac Pro.