I can't find any info on 'CBX' in the part no.., or the 39MB cache (normally 19MB).
Perhaps for a specific region market only?
Might be an idea to make a query (send info/pics) on https://www.amd.com/en/forms/contact-us/support.html
My PC- 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.