Suppose you read/tried suggestions in the 1603 help article, but the other possibility is the public amd drivers are not tested/qualified for insider builds (they have its own driver supplied).
Only Win.11 21H2 is listed as compatible in driver release notes.
Ryzen 5 5600x, B550 aorus pro ac, Hyper 212 black, 2 x 16gb F4-3600c16dgtzn kit, NM790 2TB, Nitro+RX6900XT, RM850, Win.10 Pro., LC27G55T..