Originally Posted by The Pook
early AGESA allowed advertised boost clocks, later AGESA doesn't ... so blame AMD? don't really follow.
My 9900K is advertised as a "5.0 boost" CPU but nothing ever will let it boost to 5.0 since nothing loads one core only. The only time it hits 5.0 on any core is for milliseconds while basically idle.
I've not got a 3rd gen Ryzen yet (likely when the 3950X is released) but similar tale on one work machine with a 9900K. Running Linux so it's not just a Windows thing... I think I've seen it hit 5GHz once. I've never seen it hit 5GHz on any AVX-type workload. It never hits its maximum all-core boost, either (being 4.7GHz officially, I see 4.5-4.6 under sustained all-core load) with a Noctua D15S and a pair of Noctua fans on it in a room maintained at 20*C ambient. A 2700X with the same cooler on (in the same room) spends basically its whole life at 4.2-4.25GHz, all cores loaded, which is above quoted max all-core boost clock. That will be due to whatever Asus set as defaults in the X470 PRIME BIOS, because I've gone in their once, to set the boot disk and remove the BIOS splash screen.
Advertising by boost clocks does seem a little underhanded, considering that (for both AMD and Intel) it will be highly dependent on what cooler people are using. If no
CPUs were hitting their advertised boost clocks, I'd be agreeing with people criticising AMD, but given the vast array of potential coolers and ambient conditions (not to mention tweaks on a per-model of motherboard or BIOS basis from the different manufacturers, this seems like a bit of a movable target. Someone with a large cooler living in a cold area will get much better results than someone with the stock cooler living in a hot and/or humid area.
Hm. When I get a 3rd gen, I'll take the box into work and hammer it for a while to see what it does.