AsRock's "B450M/AC R2.0 Motherboard (AM4, AMD B450, mATX)" does not come with the BIOS pre-installed to directly support the AMD Ryzen 5 5600X processor. However, you can update the BIOS to make it compatible.

To support the Ryzen 5 5600X, you must download and install a BIOS version that supports the Ryzen 5000 series processors. AsRock has released BIOS updates for B450 motherboards, and it is recommended that you visit the official AsRock website to download the appropriate BIOS version for your specific model.