Most the time it is bios or a setting. First are you on the latest bios for sure?
Next check that you are set to UEFI and not legacy. That could potentially explain why an old card works but not the Polaris cards.
What CPU do you have? If it is an APU with integrated graphics then maybe it is messing with the signal somehow going to the discrete graphics. Such as you don't have the bios setting right to initialize the discrete card first. Look for a setting that will toggle the PEG vs IGP or similar to initialize first. Your mother boards manual will have this information.
Also do you have the latest chipset driver installed? I doubt that will have bearing on this but you should regardless.
If you don't have integrated graphics or the uefi or graphic boot order doesn't help, I am really at a loss. My guess is whatever it is, is likely some simple setting in the bios or something like that. Or maybe you should try and regress back one bios revision, but I would talk to support before ever doing that. Some boards don't like that.
You should ask this question, also to tech support for your mother board and can ask it to AMD support here:https://www.amd.com/en/support/contact-email-form
Please reply back with full system specs CPU, Windows version, driver version, all hardware etc.... if you need further assistance from the community.
