Custom Resolution Utility (CRU)

[ikonomov]

(09-21-2024 03:06 PM)ToastyX Wrote:  What about refresh rates other than 144 Hz? Try 140 Hz to verify if it's allowing EDID overrides. If that works, try between 144-160 Hz.

140 Hz worked. The testing revealed the following frequencies at 3840x2160 that I was able to create and then have them available in NVCP:

in NVCP
CVT-RB: up to 99 Hz

in CRU
CVT-RBv2: up to 148 Hz
Exact: up to 149 Hz
Exact reduced: up to 155 Hz

The limiting factor for resolutions created in CRU seems to be a pixel clock of up to around 1350 MHz (155 Hz Exact reduced uses 1348.50 MHz). NVCP allows me to set the color depth to 10 bit at 155 Hz, so it seems perhaps some sort of conservative calculation is taking place that allows only resolutions that are able to output 10 bit color.

Do you know what could be the effects of using such low timings as Exact reduced?

[ToastyX]

(09-21-2024 05:09 PM)ikonomov Wrote:  140 Hz worked. The testing revealed the following frequencies at 3840x2160 that I was able to create and then have them available in NVCP:

in NVCP
CVT-RB: up to 99 Hz

in CRU
CVT-RBv2: up to 148 Hz
Exact: up to 149 Hz
Exact reduced: up to 155 Hz

The limiting factor for resolutions created in CRU seems to be a pixel clock of up to around 1350 MHz (155 Hz Exact reduced uses 1348.50 MHz). NVCP allows me to set the color depth to 10 bit at 155 Hz, so it seems perhaps some sort of conservative calculation is taking place that allows only resolutions that are able to output 10 bit color.

That must be a GPU limitation because 40 Gbps would be 1485 MHz and 48 Gbps would be 1782 MHz for 8 bpc. I wonder if that's the single-head limit for the GPU. With DSC enabled, the GPU is able to borrow other heads to support higher pixel clocks, but then the driver disables custom resolutions and EDID overrides.

(09-21-2024 05:09 PM)ikonomov Wrote:  Do you know what could be the effects of using such low timings as Exact reduced?

The main issue is the GPU won't clock down when idle if the vertical blanking is too low. You can reduce the horizontal blanking as well if you don't need HDMI audio. Try multiples of 8 for the horizontal values. You might be able to squeeze in 160 Hz if the monitor can handle low blanking values.

[ikonomov]

(09-21-2024 06:11 PM)ToastyX Wrote:  The main issue is the GPU won't clock down when idle if the vertical blanking is too low. You can reduce the horizontal blanking as well if you don't need HDMI audio. Try multiples of 8 for the horizontal values. You might be able to squeeze in 160 Hz if the monitor can handle low blanking values.

I found your post here which helped me to understand that it's the Nvidia that's likely rejecting the resolutions in the EDID, but when I use the values you provided the resolution is still being rejected. Maybe they have changed something in the latest drivers or possibly it's something specific to HDMI 2.1 or the monitor's firmware?

The lowest accepted horizontal blanking that worked was 56 pixels but strangely it locks the color depth to 10 bit. Increasing it to at least 64 allows selecting either 8 or 10 bit as normal but if it's less than 80 (the value used by CVT-RBv2) it results in displaying blank screen at 720p. The highest resolution that I was able to squeeze in below 1349 pixel clock (turns out it's exactly that value) is 158 Hz using 80 pixels of horizontal blanking. I increased the vertical blanking as much as possible and the included screenshot shows the best setting that I came out with, maybe somebody will find it useful. Thank you for your help.

   

Edit: The GPU (RTX 3070) seems to be able to clock down normally when idle. I found no other issues reported here.

[Macak]

Hello guys.
Im having problem and i hope u wiil help me to solve.
I have asus pg279q monitor.
I want to make custom refresh rate at 130Hz.
When i do that i have out of range error on my screen when i set that refresh rate.
My monitor at default have 24hz,60hz,85hz,100hz,120hz and 144hz refresh rate choices.
I dont get it why I get "out of range" error at 130hz?
Any tips pls?What I do wrong?
Tnx in advance.
cheerZ

[ToastyX]

(09-22-2024 04:27 PM)Macak Wrote:  Hello guys.
Im having problem and i hope u wiil help me to solve.
I have asus pg279q monitor.
I want to make custom refresh rate at 130Hz.
When i do that i have out of range error on my screen when i set that refresh rate.
My monitor at default have 24hz,60hz,85hz,100hz,120hz and 144hz refresh rate choices.
I dont get it why I get "out of range" error at 130hz?
Any tips pls?What I do wrong?
Tnx in advance.
cheerZ

Monitors with NVIDIA's G-SYNC processor usually don't support custom refresh rates. You shouldn't need it with G-SYNC anyway. Just cap the frame rate if you want more consistent frame rates.

[ikonomov]

As a continuation to my previous post, out of curiosity I decided to dig a bit more looking for further discussion on potential issues with such low timings. Testing for these showed no such problems on the XG27UCS monitor.

No issues with frame skipping (likely only a problem with older monitors): https://forums.blurbusters.com/viewtopic...205#p91601

No noticeable change to inverse ghosting, perhaps helped by the well tuned variable overdrive settings of this monitor: https://forums.blurbusters.com/viewtopic...664#p86652

Using lower vertical blanking should have practically imperceivable effect on input lag at 158Hz. I tried to detect some difference compared to using CVT-RB2 timings or increased vertical totals which I can get at 1080p/160Hz, but if there is a difference I can't tell without a measuring tool: https://forums.blurbusters.com/viewtopic...501#p97907

Some futher tests here.

[ninjabyte587]

windows 11 24h2 seems to have changed something; i cant get my refresh rate to only remain 180hz

[funkerwolf]

Good night, am I the only one who noticed that after version 32.0.101.5768 there is no more monitor overclocking on 11th generation Intel integrated graphics? I can't set 75 hertz on my resolution 1920x1200, tried all options, only rollback to 32.0.101.5768 helps.
MoBo MSi B560M PRO-VDH - latest bios
CPu Intel Core i5-11500
Lenovo ThinkVision T23d-10 - hdmi link
Windows 11 24h2 26100.1876
The problem appeared since version 32.0.101.5971

[ToastyX]

(09-24-2024 12:12 AM)funkerwolf Wrote:  Good night, am I the only one who noticed that after version 32.0.101.5768 there is no more monitor overclocking on 11th generation Intel integrated graphics? I can't set 75 hertz on my resolution 1920x1200, tried all options, only rollback to 32.0.101.5768 helps.
MoBo MSi B560M PRO-VDH - latest bios
CPu Intel Core i5-11500
Lenovo ThinkVision T23d-10 - hdmi link
Windows 11 24h2 26100.1876
The problem appeared since version 32.0.101.5971

Is there an HDMI data block in the CTA-861 extension block? If not, the pixel clock will be limited to 165 MHz. If there is an HDMI data block, is the max TMDS clock higher than the pixel clock for the custom refresh rate? If not, the driver might ignore the custom refresh rate. Ideally it should be set to 340 MHz for HDMI 1.4.

[ToastyX]

(09-23-2024 10:23 PM)ninjabyte587 Wrote:  windows 11 24h2 seems to have changed something; i cant get my refresh rate to only remain 180hz
https://i.imgur.com/a5vJ7tx.png
https://i.imgur.com/6FqHtub.png

What GPU? What data blocks are in the extension block?