Question Gigabyte B450 Aorus M not posting, red VGA light on


Sep 15, 2014
Upgraded my computer today from my ancient i7 4770k to a Ryzen 3700x. Obviously this meant a new mobo and ram as well. I got a Gigabyte B450 Aorus M to go with it, and the instal went fine. But now I am not getting any post, nothing to the screen at all. The little red LED labelled VGA is lit, but I can't figure out why. I have a GTX 1080 that I know works fine because I've been using it for a few years now. I've tried resetting the mobo battery, resetting the PCI power cables, booting with and without the GPU installed, with an HDMI cable, a DisplayPort cable, HDMI in the mobo w/o the gpu, etc. I genuinely don't know what else to do.

The super weird thing is that I was able to get it to boot once to windows with everything installed, but afterwards when I moved the pc to my desk without changing anything and plugged everything in it doesn't boot anymore.