PC won't post, need advice

I'm building an HTPC, about half of the parts (including the processor) were taken from an old build. I put everything together, started it, lights and fans came on but nothing displayed. I put everything into PCpartpicker and it flagged the bios being out of date for the CPU without an update.

CPU: Ryzen 3 3200G MBU: Asrock A-320M HDV

So basically, the way I see it my options are either update the bios without another CPU, or return the MBU and get one that will work. I'm open to either option but I have no idea how to update the bios or if this MBU will allow me to do so without another CPU.