PS5 120Hz 4k limited to 8bit limited range HDR HDMI 2.1

[MommaB]

Hi, new owner of the PG32UQ here. Happy with it so far but one thing is bugging me. Hopefully support can help me with some settings to make this work. Or other PG32UQ or Asus 120+Hz 4k HDR monitor owners can chime in with their experience and verify if this is working correctly for them.

PS5 has a limited output of 4:2:2 at 4k 120Hz over HDMI 2.1. However, it should be possible to do 10 bit. Mine will not go higher than 8 bit.

I have tested the Asus cable, the PS5 cable and a shop-bought ultra speed hdmi cable and both ports of the monitro, and all give the same results.

I tested 120Hz 4k mode with Doom Eternal. Results in the OSD of the monitor (Menu>System Setup>Information):

HDMI 3840x2160@120Hz
HDR Console Mode
Color Depth - 8bit
Format - YCbCr 422
Range - Limited Range
EOTF - 2048
VRR - No
FW version - V024



I tested 60Hz 4k in other games and the menu of the PS5 and note that it does go up to 4:4:4 Full range RGB and even 12 bit:

HDMI 3840x2160@60Hz
HDR Console Mode
Color Depth - 12bit
Format - RGB 444
Range - Full Range
EOTF - 2048
VRR - No
FW version - V024



PS5 settings (many variation tested but all with same or worse results):

[Ecmslee]

That's expected. PS5 HDMI bandwidth is currently capped at 32Gbps. 4K 10-bit 4:4:4 120Hz requires 40.09 Gbps. See here:
https://youtu.be/rpA4HfikU4w

Your monitor should be fine. It's just a limitation of the PS5. You can get the full capability out of your monitor if you can connect a reasonably modern PC to it.

[MommaB]

That's expected. PS5 HDMI bandwidth is currently capped at 32Gbps. 4K 10-bit 4:4:4 120Hz requires 40.09 Gbps. See here:
https://youtu.be/rpA4HfikU4w

As I said, and also linked in my post (here), I know PS5 is limited to 4:2:2 at 120Hz in 4k. But it should go up to 12 bits. Mine only goes to 8 bits which is too low. If you watch the video you linked he also mentions the same at the 6:00min mark (here)

What is the info your screen is reporting if you play a 120Hz game on PS5?

[MommaB]

Your monitor should be fine. It's just a limitation of the PS5. You can get the full capability out of your monitor if you can connect a reasonably modern PC to it.

Hi yes thanks again for the edit as well. I'm not too worried the monitor wouldn't perform well with a PC.

I do want to the monitor to perform as advertised and within its capabilities when connected to the PS5.

[Ecmslee]

This appears to be a known issue of HDMI sink devices misreporting YCC 4:2:2 bit rate. The problem is not exclusive to this monitor or the TV in the HDTVTest video. As you can see at the 6:00 mark on that video, the PS5 is in fact outputting YCC 4:2:2 12-bit but the TV info shows it as 8-bit.

Here is a relevant quote from the LG C9 FAQ on AVSForum:

Problem: The TV is reporting that image has 8bit instead of 10/12bit;
Conditions: -;
Cause: When the TV is getting a 4:2:2 HDR signal it is always reported as 8-bit even though it is receiving 12-bit. This is a technical limitation of HDMI. The only way to verify what bit-depth you are getting is to use test patterns. It's the same reason why Dolby Vision is reported as SDR. Because the TV doesn't actually "know" what it is getting.

As long as your HDR video is not exhibiting extremely visible banding, you can assume that your PS5 is outputting at higher bit rate.