The "ROG Strix B650-A Gaming Wifi (AM5, AMD B650, ATX)" motherboard from ASUS is compatible with the "Gigabyte AMD Radeon RX 7800 XT" graphics card.

Here are the most important points that confirm compatibility:
- The graphics card uses the PCIe 4.0 standard, which the motherboard supports.
- The motherboard has an AM5 socket and supports the latest AMD processors, which is also required to use the RX 7800 XT.
- There are no specific restrictions or problems that would preclude compatibility between this mainboard and the RX 7800 XT graphics card.

However, it is always advisable to update the motherboard's BIOS to ensure that all newer hardware components are properly supported.