msi b450-a pro max

So I've been putting together my first new build with the following specs: Motherboard: MSI B450-A Pro Max CPU: Ryzen 7 3700x GPU: EVGA GeForce GTX 1080 RAM: Corsair Vengeance LPX 16GB Power Supply: Cooler Master - MWE Gold 750W ATX12V 2.31 80 Plus Gold Modular Everything is powering on, but...