According to available information (because AMD does not provide publicly info how their products work), gpu clock should be set between game clock and boost clock (while gaming) for Navi architecture.
But Radeon drivers (adrenaline) have boost clock always set to 2100, which is in my opinion incorrect. It is very obvious becuase I have Sapphire 5700XT that should boost "up to 1925MHz", but it boosts indeed much more higher - to 2100MHz which is set in drivers.
E.g. common boost is e.g. 1950 in lighter load, with death boost spikes to 2100Mhz, max should be 1925 according to manufacturer and GPU-Z.
And it explains various issues and random behaviour of crashes. Crash occurs often when sudden death boost occurs. And it depends on quality of chip if card crashes at these boosts, so it explains why some people do not have any issues - depends on distribution of gpu chips.
I underclocked my card in Adrenaline and now it is much more better. I am testing it yet.
Still I think that something is massively broken in drivers now, maybe all boost architecture, becuase I read in some articles that card does not have clock set? I do not know AMD does not provide info how things work.
I was able to Google info from AMD site, AMD says
Boost Clock Frequency is the maximum frequency achievable on the GPU running a bursty workload. Boost clock achievability, frequency, and sustainability will vary based on several factors, including but not limited to: thermal conditions and variation in applications and workloads.
Therefore AMD driver setting 2100MHz boost frequency for all 5700XT cards must be incorrect. AMD drivers cause frequency higher than manufacturer boost frequency normally with boosts going straight through the roof towards deadly 2100MHz.
Just for comparison from what I read on sites, it looks like AMD boost frequency is maximum frequency (there is always up to, e.g. up to 1905MHz in specification) whereas Nvidia technology boost frequency means minimum boost frequency and is dynamically overclocked to hit power and temp target.
So again if this is how it works - Radeon drivers should not set boost frequency 2100MHz for each and every 5700XT card.
How most places explain the Core / Game / Boost Clocks (including AMD.com) isn't ACTUALLY how Radeon Architecture works.
As a note... the listed Clocks are just the Guaranteed Clocks by AMD Quality Control.
That means that if you purchase an RX 5700 XT., it is guaranteed to operate at the listed Frequencies in those user cases.
Now the designation of Core / Game / Boost can be a little misleading to Consumers.
Core Clock is literally the "Lowest" Possible Frequency you can expect to see when the GPU is Under-Load... and you can more-or-less ignore this because it'll never actually hit this unless you case is absolute garbage with no airflow.
This is just AMD covering their behind, for people with bad rigs.
So consider that a "Worst Case" Scenario Clock.
Typically speaking the new "Game" Clock is what AMD Guarantee while gaming., this is more-or-less how low you can expect the Frequency to go IF you have the Poorest Quality Silicon AND Thermal Throttling has kicked in.
The Boost Clock is what you can ACTUALLY expect your GPU to typically operate at.
Generally speaking, it will try to operate at the Boost Frequency and Throttle down to the Game Frequency as required.
Oh and keep in mind this is with the Default Fan Curve, which is set to Max out at 40% in Reference Models as AMD have focused on Noise over Performance this Generation.
I'd argue that tweaking that to 60%, which only marginally increases the Noise Ceiling from 38dB to 44dB will actually result in most Lower Quality Silicon more commonly hitting the 1905MHz "Boost" Clock without Throttling.
Now as a note., 1905MHz listed is what the RX 5700 XT will Default to as it's Boost Clock... but Navi 10 has XFR Support... that means if it has the Thermal Headroom (say like my RX 5700 XT Reference, hitting 1905MHz while comfortably maintaining 65c at 35% Fan Speed), the Drivers will say "Oh hey, you've got a lot of Headroom... let me just adjust the Boost Frequency for you"
Remember the Fan kicks in at 65c... it only Throttles Frequency at 81c.
As such, more often than not., it'll actually boost my GPU to 2105MHz as it can maintain that with 40% Fan at ~78c, which for the Drivers is still "Within Specifications, so all is Good".
NVIDIA Drivers actually have done something similar, which they call Precision Boost... where whenever there is Thermal and Power Headroom; it'll boost beyond the listed Boost Frequency (quite a bit beyond in-fact).
So you're getting that "Automatic" Overclocking, without even realising it.
It's why you should be very wary of NVIDIA Benchmarks too... because they send the best Silicon to Reviewers, meaning they'll typically boost to a "Best Case" Performance; where-as AMD have a habit of sending w/e Quality Silicon they happen to have produced; and also typically limit Press Drivers to the Specifications, without Manual Overclocking.
Thus it tends to be a showcase of how different the Cultures and Attitudes are between the two GPU Designers.
There's nothing wrong with your RX 5700 XT or Drivers... rather you just have Better Quality Silicon.
I'd say be happy with that., as there are quite a few who complain that their Cards are temperatures far too high (81c) while gaming and their barely getting the Game Clock.
Still that's just how the Silicon Lottery works...
I mean while I tend to have been pretty lucky with my AMD GPUs., my Ryzen CPU is abysmal Silicon Quality; as it basically isn't capable of going above it's Listed Clocks (3.5 - 3.6GHz) where-as there are others who contently hit 3.9-4.0GHz with theirs.
Can't complain as, well its achieving what AMD Promised on the Box and Website; but still can't help but be a little disappointed.