Hardware unboxed (HUB), just like techpowerup (TPU), disable Smart Access Memory (SAM).
SAM adds 10-20% performance in this game from my testing.
I'm not sure why they choose to disable it when it is enabled by default and they use Ryzen processors.
SAM has been disabled for HUB since their first 6800 XT /6900 XT reviews, TPU the same. That affects all their results for every graphics card review and game benchmark they do. Something to remember when you look at their results but this is often overlooked.
Meanwhile, the following sites have RDNA2 ahead in Halo and they test the same open world demanding areas online (like HUB) which represent a worst case scenario. They are using the Steam version of the game according to the testing notes.
- Sweclockers
- PCGamesHardware
- Computerbase
- Kitguru
It is not clear if Kitguru used ReBar, but the others had SAM/ReBar enabled as there is no logical reason to disable it for AMD graphics cards.