Ever since i upgraded from a 1070 to 4070 Ti (couple of months ago) i'm experiencing sporadic black screens after booting up the PC. I see the BIOS post followed by the spinning balls circle, and then it stays black. It looks like it booted fine, as there is nothing unusual reported in the Windows log files. I have to shutdown by holding the power button for a couple of seconds and then it boots fine (usually). Mind you, i did a clean install of Windows 2 days ago and it's still happening.