Custom Resolution Utility (CRU)

[ToastyX]

(06-02-2026 10:03 PM)Esc_Jim Wrote:  

(06-02-2026 08:20 PM)ToastyX Wrote:  If you mean Intel's .hex format, no, CRU doesn't support that. The .bin file is plain binary. CRU can also export a .txt file with hex values.

Thanks for the info, and for staying with me. Either file type would be OK with a little massaging.

I've run CRU.exe and while I don't have the device yet, I do get the EDID info from my two attached monitors. If I want to get the 'auto hdtv' settings into a text or bin file suitable for the breakout board, what step are needed? It wasn't clear to me if I needed to have the board attached, or if I could just export the settings as a generic file, or if I needed to create settings based on one of my two monitors or...?

You can start with an existing monitor. You can delete all the resolutions and just add the ones you want. You can add detailed resolutions with Automatic HDTV timing for resolutions such as 1920x1080 @ 60 Hz and 1280x720 @ 60 Hz. If you need more slots for resolutions, add them in a CTA-861 extension block. HDMI also requires the HDMI data block in the CTA-861 extension block to go beyond 165 MHz pixel clock, but the TI TFP401 is a DVI receiver and doesn't officially support more than 165 MHz pixel clock anyway, so you don't actually need anything other than the resolutions. Then you can export the file.

[marcgii]

Hi new user here. Are 5k resolutions not supported at all? My monitor's native resolution is 5120x2880

[ToastyX]

(06-19-2026 07:53 PM)marcgii Wrote:  Hi new user here. Are 5k resolutions not supported at all? My monitor's native resolution is 5120x2880

5K resolutions are supported in DisplayID extension blocks.

[MUC]

(06-19-2026 07:53 PM)marcgii Wrote:  Hi new user here. Are 5k resolutions not supported at all? My monitor's native resolution is 5120x2880

They are supported. But you need to define or edit them within a DisplayID data block. Please refer to the Apple Studio Display XDR example in the attachment.

[marcgii]

(06-19-2026 10:42 PM)MUC Wrote:  

(06-19-2026 07:53 PM)marcgii Wrote:  Hi new user here. Are 5k resolutions not supported at all? My monitor's native resolution is 5120x2880

They are supported. But you need to define or edit them within a DisplayID data block. Please refer to the Apple Studio Display XDR example in the attachment.

Thank you. I'm trying to see is I can get 5k 180hz (or 165) working with DP1.4 with DSC. It apparently only works with DP2.1 and it's unclear if it's hardware limitation or firmware. Samsung support has no idea if it should work or not with DP1.4.

Any idea if it's possible?

Edit. I can't create custom resolutions using the Nvidia app for this monitor. And I think whatever is causing that is also preventing CRU from making any changes. I've tried editing some resolutions. But doing so has no effect.

[MUC]

Quote:I'm trying to see is I can get 5k 180hz (or 165) working with DP1.4 with DSC.

Yes, in theory, that works.

5120 x 2880 @ 180 Hz RGB 10-bit (CVT-RB) = 2984.25 pixel clock = 345% HBR3 ... with DSC 8.75 bpp OK

Which Samsung monitor do you have? What is its native refresh rate?

However, Nvidia drivers for graphics cards with DisplayPort 1.4a HBR3 have a quirk where they ignore EDID overrides if the pixel clock required for the output signal exceeds 1350 MHz. This is the case for your setup. Consequently, you cannot use CRU, or rather, the changes have no effect.

[marcgii]

(06-20-2026 12:59 AM)MUC Wrote:  

Quote:I'm trying to see is I can get 5k 180hz (or 165) working with DP1.4 with DSC.

Yes, in theory, that works.

5120 x 2880 @ 180 Hz RGB 10-bit (CVT-RB) = 2984.25 pixel clock = 345% HBR3 ... with DSC 8.75 bpp OK

Which Samsung monitor do you have? What is its native refresh rate?

However, Nvidia drivers for graphics cards with DisplayPort 1.4a HBR3 have a quirk where they ignore EDID overrides if the pixel clock required for the output signal exceeds 1350 MHz. This is the case for your setup. Consequently, you cannot use CRU, or rather, the changes have no effect.

Oh so this whole endeavor was doomed from the start. I have a RTX4090 and I was using it with the Samsung G80HF.
Funny thing is the monitor has a popup that keeps telling me to set it to the optimal resolution of 5k180hz.

[ninjaguy]

why when i do the steps to get a custom resloution it doesnt work anymore i wanted to add another resloution and when i restart pc it just gives 2 resolutions and 60 hz and 40 hz in windows display settings even though i downloaded it yesterday and it worked now its not

[ToastyX]

(06-21-2026 09:49 PM)ninjaguy Wrote:  why when i do the steps to get a custom resloution it doesnt work anymore i wanted to add another resloution and when i restart pc it just gives 2 resolutions and 60 hz and 40 hz in windows display settings even though i downloaded it yesterday and it worked now its not

Can you show me what you're doing and tell me what monitor and GPU you have?

[marcgii]

I asked Claude to analyze my monitor EDID info and why I can't achieve the rated refresh rate (5k180) even though DSC clearly works on both HDMI and DP1.4. The explanation it gave of Samsung screwed up the EDID sounds plausible. But can anyone here confirm it is likely an EDID problem? The numbers it cites here are correct.

Quote:Your monitor's own Display Range Limits descriptor in the base EDID block declares a max pixel clock of only 2550 MHz. But the actual 180Hz timing in the DisplayID block needs 2932.5 MHz. The monitor is contradicting itself — one part of its EDID says "I support up to 2550MHz," and another part lists a timing that needs 2932.5MHz. There's also a horizontal frequency mismatch (range limits say 510kHz flat, but 180Hz needs 532.8kHz — over that too).
This is precisely the kind of internal EDID inconsistency that makes a driver throw out the higher mode: Nvidia's driver reads the Range Limits descriptor as the monitor's own stated ceiling, sees the DisplayID 180Hz timing exceeds it, and drops it as invalid — while 120Hz (1978MHz, comfortably under 2550MHz) passes cleanly and gets exposed. That lines up exactly with what you're seeing: 120 works, 180 doesn't, on both DP and HDMI, because this is an EDID-side defect, not a link-bandwidth one.