Custom Resolution Utility (CRU)

[bobithtidus]

(02-08-2025 07:41 PM)ToastyX Wrote:  

(02-08-2025 06:52 PM)bobithtidus Wrote:  For DSR, and not using the monitor's DSC, I can tell the quality difference between DSC on and off, and the only way to turn off DSC is using 2.1 AV, and I think 240 hz. The reason why i created a custom resolution is to take advantage of DSR and turn off DSC. As for second profile I might try with 1.4 to see what is the deal with that. Also there is certainly difference in HDR, which is the mode I am primarily using, the HDR seems to tone map differently, which is why I am wondering the monitor is doing something cheap like using internal adjustment to downgrade certain things to be able to do 240hz, just like how DSC is a visual downgrade over the full bandwidth.

Edit: So I tried with 1.4 dp, and the same thing showed up the profile drop down box always default to GSM780A and I have not way of activating GSM780B which is the newer version.

CRU normally doesn't include the range limits unless it's DisplayPort with adaptive sync. GSM780B doesn't mean newer. It's just a device ID. Maybe GSM780B is with DSC enabled/disabled, or they could have changed the ID in the firmware update.

If you're seeing a quality difference, either the output color depth and format are not the same, or the monitor is doing something differently without DSC. 3440x1440 @ 240 Hz won't be possible with DisplayPort without DSC. With HDMI 2.1, it should be possible without DSC up to 10 bpc if the FRL rate is 48 Gbps. If it's only 40 Gbps, you won't be able to get 10 bpc, which is needed for HDR, so that could cause a difference if you're only getting 8 bpc.

Yea did some further testing with 1.4 dsc, indeed the B version became active, but the image quality is ass, even with lower HZ and worst part changing the HDR static metadata did nothing, just clipping past 600 nits, so switched back to 2.1 AV and turn off all the DSC option in HDMI 2.1, now image quality look much better, but weird part is it gets even better at below 120 Hz, now the HDR just look right, seems to be monitor limitations, sacrificing something if you want to go above the 655 MHz limit, kind of suck but I actually prefer to play on 100 Hz then 240 hz with gimped details. Anyhow using full bandwith over DSC always look better, might be a small or no difference to some on that lossless thing, but a big difference to me, thanks for your input.