Question BIOS booting issues

Aug 2, 2020
So I just finished a new build:

Ryzen 7 3700x
MSI Radeon 5600XT
MSI X470 Gaming plus max
TT Smart 600w PSU
Corsair Vengeance (2)3000hz / (2)3200hz 32gb (4 sticks)

Everything seemed to be working fine. I went into BIOS yesterday and activated an XMP profile and set my RAM to 3000. Today I was working on troubleshooting AMD's PVT and one of the suggestions was to turn off any OC settings.

I restarted to go into BIOS, smashing my delete key, in an attempt to turn off the XMP profile except for my PC won't boot. The RAM LEDs turn on, my keyboard and mouse light up but BIOS doesn't boot.

After about 20 minutes of resetting CMOS and trying other things, I've come to the conclusion that the PC only fails to boot when I try to enter BIOS. If I power up and don't touch anything, the PC boots fine, although the bios screen doesn't flash.

What could cause my computer to not boot only when attempting to enter BIOS? Faulty MB? Faulty CPU?

Thanks in advance for any help!