Ever since updating to firmware 1402 I have been unable to get any picture from my RTX 3090. I pull out and insert the HDMI cable to get the TV to detect the PC and that works to get image but input signal plus is disabled that way. Turning input signal on results in no input screen. Using any other than HDMI port 4 works fine with input signal plus but these don't have the benefits of HDMI 2.1.
I have a CX too and the RTX 3090 works fine with ultra HD deep colors at 4K 120 Hz 10 bit HDR.
It worked on the previous firmware and I hope there will be no unpleasant surprises with HDMI 2.1 and Xbox Series X and PS5 next month.
In my case most issues got resolved with firmware 1403 and a certified hdmi 2.1 cable. None of the non certified cables I tried worked, even with the latest FW and drivers. I'm using a gtek 8k certified cables without issues on 4k 120 Hz with vrr, or 8k at 60 hz
Now that I have a Xbox Series X, on a hunch I tried again with the Xbox Series X HDMI cable and this time it worked.
Weird thing is when I switched back to the older cable it worked too. T.T
I get flickering with the non Series X cable on my LG CX and none with the Series X cable when using Xbox Series X at 4k 120 hz 10bit HDR so I suspect the quality of the HDMI 2.1 cable might be at play here.
This is with Firmware 1460.
I ordered some certified HDMI 2.1 cables and hopefully this will sort everything.
