NVIDIA 535.43.03 and breaks DDC/CI for some monitors

[digitaltrails]

I just upgraded my Nvidia driver from 525.116.04 to 535.43.03 and ddcutil stopped working for one of my two monitors, an HP ZR24w. See https://forums.developer.nvidia.com/t/nvidia-535-43-03-breaks-ddc-ci-for-some-monitors/257559.

My newer LG monitor works fine with DDC/CI and 535.43.03, so the newer driver’s DDC/CI implementation still works with some monitors. Both monitors are connected via DisplayPort to an Nvidia 1650 SUPER, but the HP ZR24w is using a DisplayPort to DVI connector (DVI at the monitor end), where as the LG is DisplayPort at both ends.

[digitaltrails]

I was using a passive passive DP-DVI cable. A successfully workaround is to use HP ZR24w's DisplayPort connector with a DP-DP cable.

[digitaltrails]

Because of another issue with the driver (not DDC related) I've reverted to Nvidia driver 525.116.04 - hopefully they will eventually fix their driver.

[digitaltrails]

Nvidia driver 545.29.06 with kernel 6.7.2 and either ddcutil 1.4.1 or 2.1.4 seems to be working OK now. Thats with a passive DP-DVI cable and a DP-DP cable.