ASUS released a bios series that adds AMD's marketed SAM, or really; Resizable BAR support to various motherboards. The thing here us though, these are for the Intel Z490 chipset. 'Smart Access Memory' was initially only supported on AMD motherboards. Intel itself has not yet reported on support for this feature.
Bios version 1002 appeated last Friday and is in beta status. ASUS did not add a changelog to the bios update, Tom's Hardware noticed that the update adds support for the Resizable BAR function and Above 4G Decoding, the u[dates seem to become available to the more premium motherboards.
The website reports that it is unclear whether Resizable BAR actually works on the motherboard in combination with AMD's RX 6000 GPUs as SAM also requires a Ryzen 5000 series processors in the shape of AMD's wording. It might just be for future compatibility support.
ASUS releases beta bios beta versions with SAM - Resizable BAR function for Intel Z490 motherboards