I received my 4070 Super Founder's Edition card yesterday, installed it this evening. Removed drivers beforehand with DDU then shut the PC down. Removed the old 3070 and inserted the 4070 Super in the same slot and connected the 12-pin power cable and HDMI cable. Started it back up - nothing on screen at all.
Switched the HDMI cable into the motherboard HDMI socket and got into Windows, no sign of the 4070 in Device Manager. Updated the BIOS (board is a MSI Z690-A Pro), still nothing.
Any further suggestions more than welcome...