I can confirm, on a 2008 MacPro with Apple ROMed GTX680, that the nvidia 440 drivers bundled with the 20.04 beta release show the same behavior. The Apple Cinema HD display LED comes on (indicating that the driver loses contact with the display) as nvidia drivers are loaded and nvidia-modeset executes.
I can confirm, on a 2008 MacPro with Apple ROMed GTX680, that the nvidia 440 drivers bundled with the 20.04 beta release show the same behavior. The Apple Cinema HD display LED comes on (indicating that the driver loses contact with the display) as nvidia drivers are loaded and nvidia-modeset executes.
Apr 4 14:35:03 howarth-MacPro kernel: [ 57.436235] nvidia-modeset: WARNING: GPU:0: Lost display notification (0:0x00000000); continuing.