Question about ASUS ROG Strix X570-I Gaming

I tried to update the BIOS for several hours today. Unfortunately, I never got past the POST and got an orange LED (Problems DRam). After connecting a beeper, I got one long and two short beeps (No memory detected). I tried (pretty much) everything but to no avail. I tried it with a 2700x, which as far as I know is supported. I had four different memory modules in it, some of which I saw in the QVL. I also jumpered the CMOS and disconnected it physically. Changing the PSU didn't help either. Does anyone here have any ideas? At the moment I'm getting a bit desperate and am almost leaning towards a broken mainboard...