Is this my issue you think? You can click on my name and see my post, but I have a b450a pro mobo, rx580 8gb, and ryzen 3 1200 that works - but when I put in ryzen 5 5600x all i would not get post - not lights and fans running and 'boot' led lit up on mobo.HI guys, there is another way to get around this secure boot and OLD G Cards.
What you do is DO NOT throw away that old 2000 or 3000 series CPU when you upgrade to a 5000 series + CPU. Then when you buy one of these NEW motherboards DO NOT install the 5000 series + CPU, instead stick in your old CPU, I used a 2700X and it allowed me to boot up and get into CMOS settings (BIOS). I then changed the settings which has caused all of the problems, secure boot, and PCIE 4 (Change to PCIE 3 and not Auto) then save settings. drop your new CPU in and 99.9% of the time it will boot up and your into the warning screen asking if you want to, "Press F1 for setup, F2 to continue to O/S". or something along those lines, or just hit Del, once you have gone through POST, which takes longer the first time you boot up. Monitors should not matter if your on a PC monitor, TV's may be slightly different depending on its age.
I was about to return this but do you think it could fix the issue?