This driver is not intended for gaming or workstation workloads, it's a special beta for miners. Lots of AMD's architectures are supported, from the five-year old Radeon HD 7700 series to the new Radeon RX Vega series.
Legit Reviews tested the driver and they conclude this beta helps to keep all Polaris and Vega cards from having issues with larger DAG files:
The Radeon RX 480 went from 24.6 MH/s at DAG #130 and dropped down to 14.8 MH/s at DAG #199. With the new driver the performance went up by a hair and performance at DAG #199 is shown to be 24.8 MH/s according to Claymore’s benchmark script. The performance of the Radeon RX 580, Radeon RX Vega 56 and Radeon RX Vega 64 remained the same at DAG #130 and DAG #199 with the new block chain driver! AMD has greatly improved the DAG performance issue! We did notice that the changes implemented by AMD slightly increased the power draw of the system with the new improvements, but if the hashing power dramatically increases that doesn’t bother us one bit.