The ASUS PRIME B450M-A II motherboard is compatible with the AMD Ryzen 5 5600 processor, as it supports the AM4 socket, which is suitable for this processor generation.

Regarding the Gigabyte Radeon RX 6600 EAGLE graphics card: The motherboard supports PCIe x16 slots, which allows the use of this graphics card. However, it is important to ensure that the system provides sufficient power and cooling for the graphics card.

Overall, both components should work together without any problems.