Like Slob said, it will support it, but only if you're upgraded to that BIOS or beyond. Otherwise it won't boot.
The latest BIOS is F56. You can do this manually, if you know how, but Gigabyte does provide a motherboard support utility that will automate this. Just download the
App Center app (the .exe) from this page, and after installing it & launching it, now from within the app itself, you can choose the
BIOS app as a plugin app to download into the network of apps that App Center will manage. Then you launch the BIOS app, and update. Make sure there are no threats to disruption of the update once you initiate it. Don't turn off the computer, make sure nobody throws a breaker. Otherwise you can brick your computer:
Lasting Quality from GIGABYTE.GIGABYTE Ultra Durable™ motherboards bring together a unique blend of features and technologies that offer users the absolute ...
www.gigabyte.com
What is the RAM you purchased, though? That motherboard will only support up to 3200 MHz. So if you bought a 3600 MHz kit, it won't support the RAM's overclocked AMP presetting, and it will default down to the JEDEC standard of 2133 MHz.
Running a 5900X on 2133 MHz RAM is bad enough to even make me wince, and I'm pretty forgiving. Even if it is 3600 MHz+, your RAM kit might have a secondary, lower frequency AMP presetting within the 3200 MHz parameters, although there's no guarantee it will actually run on that motherboard. Because those older A320M boards are less likely to successfully maintain these overclocks. If not, your only recourse would be to learn about RAM overclocking so that you could manually tune the RAM up to something that would hopefully be stable, assuming you're willing to do that.
I would also advise installing the free HWInfo if you get everything up and running so that you can monitor your temps. That motherboard has only a 6-phase VRM. As My Spot is suggesting, the CPU is definitely a bit overmatched for it. You'll probably be alright, but I'd keep an eye on it. Not just the CPU temps, but the motherboard temps on the right-hand page in the Sensors section of HWInfo.
Start to analyze your hardware right now! HWiNFO has available as an Installer and Portable version for Windows (32/64-bit) and Portable version for DOS.
www.hwinfo.com
Consider a motherboard upgrade.