AMD Ryzen 7 3700x supported the following chipset X570, B550, A520, X470, and B450. For X470 and B450 chipset, you need to update BIOS. In this guide, I have only picked X570 and B550 chipset based motherboard. If you are low in budget then you can pick B450 or X470 chipset based motherboard.
Going by this only x470 b450 need the bios update.
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