Question PC not booting, quick CPU led flash

Jun 4, 2020
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After successfully (kind of) finishing my first build it boots and opens the bios, after setting my boot drive and saving my settings the PC turns off.
I try turning it on again but after I did none of the fans were spinning and an LED marked as the CPU status led flashed red for a quick second.
Does anyone know what this means and how can I solve it?

Using a Ryzen 1600 af with an Aorus b450 m