Adding/Using HiDPI custom resolutions

[Rymek]

Ok so I managed to do it. It's not HiDpi, but I was looking for native resolution of 5120x1440, which I could enable by default, but everything was fuzzy as hell and not really clear. So I had to add this custom resolution because of pixel clock was set incorrectly (value around 100 less than it should be according to switchresx on my macbook pro 15 when I connected the monitor).

I think it has something to do with radeon card that by default has low pixel clock (i've read something about it on the internet). Don't know if it's the issue, but finally got it working:

 

[joevt]

Ok so I managed to do it. It's not HiDpi, but I was looking for native resolution of 5120x1440, which I could enable by default, but everything was fuzzy as hell and not really clear. So I had to add this custom resolution because of pixel clock was set incorrectly (value around 100 less than it should be according to switchresx on my macbook pro 15 when I connected the monitor).

I think it has something to do with radeon card that by default has low pixel clock (i've read something about it on the internet). Don't know if it's the issue, but finally got it working:

Are you saying (with all other numbers the same) that 469.180 MHz is blurry and 469.190 MHz is not? Very strange. I remember another Mac user complained about blurriness - his display was only 3440x1440 though - a Samsung Monitor CJ79.

patch-edid.rb

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Can you post the override file (/System/Library/Displays/Contents/Resources/Overrides/DisplayVendorID-1e6d/DisplayYearManufacture-2019-DisplayWeekManufacture-4)? Create one with the 469.180 MHz timing, and another with the 469.190 MHz timing (or include both at the same time if possible?).

In a DisplayID extension block of the unmodified EDID, 469.18MHz is represented as 46917.
Maybe they wanted 469.19 MHz, enterred 469.18 MHz because they knew that DisplayID uses an offset of 1, but their EDID editing app does the offset calculation again so the final representation is 46917? That's some keystone cops action.

 

[Rymek]

No, 469,180 is not blurry, but by default, the resolution that was detected had 329ish. Now it's fine, but I had to add custom resoltution and override pixel clock with 469,18.

Also, I couldn't set 5120x1440 via System Settings -> Displays. Had to install switchresX where the resoltuion was available, but with wrong pixel clock, hence the override, custom resolution with correct pixel clock

here are the contents of the file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "[URL][URL][URL]http://www.apple.com/DTDs/PropertyList-1.0.dtd[/URL][/URL][/URL]">
<plist version="1.0">
<dict>
    <key>DisplayPixelDimensions</key>
    <data>
    AAAUAAAABaA=
    </data>
    <key>DisplayProductID</key>
    <integer>40570</integer>
    <key>DisplayProductName</key>
    <string>SwitchResX4 - LG HDR DQHD</string>
    <key>DisplayVendorID</key>
    <integer>7789</integer>
    <key>IODisplayEDID</key>
    <data>
    AP///////wAebXqe9FAEAAQdAQOAeCJ46gnBrlBEryYOUFQhCABxQIGAgcCpwNHAgQAB
    AQEBpngAMPI4WkCwWIoArlFBAAAeAjqAGHE4LUBYLEUArlFBAAAeAAAA/QAwPR6HPAAK
    ICAgICAgAAAA/ABMRyBIRFIgRFFIRAogAioCAzxxTQEDEgQgIpAfXV5fYGEjCQcHgwEA
    AG0DDAAgALg+IABgAQIDZ9hdxAF4gAPjDwAY4wXAAOMGBQGKZAAw8jhaQLBYigCuUUEA
    AB5UPAAw8jhaQLBYigCuUUEAAB4AAAD/ADkwNE5UUUQ4QTg2OAoAAAAAAAAAAAAAAAAA
    BnARJAMAAwAURrcAAP8TnwAvgB8AnwUoAAKACQALAApTd2l0Y2hSZXNY1QAAAAAAAAAA
    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACQ
    </data>
    <key>SwitchResX backuped settings</key>
    <dict>
        <key>DisplayProductID</key>
        <integer>40570</integer>
        <key>DisplayVendorID</key>
        <integer>7789</integer>
    </dict>
    <key>default-resolution</key>
    <data>
    AAAUAAAABaAAPAAA
    </data>
</dict>
</plist>

 

[joevt]

No, 469,180 is not blurry, but by default, the resolution that was detected had 329ish. Now it's fine, but I had to add custom resoltution and override pixel clock with 469,18.

Also, I couldn't set 5120x1440 via System Settings -> Displays. Had to install switchresX where the resoltuion was available, but with wrong pixel clock, hence the override, custom resolution with correct pixel clock

here are the contents of the file:

Whatever timing you saw that was 329ish was probably not 5120x1440 (check the "active" pixels and compare with "scale to").

This override file (product 40570) appears to be for HDMI connection. The AGDCDiagnose you sent before was for DisplayPort (product 40571). Please send AGDCDiagnose for the HDMI port so we can see the unmodified EDID. Each port of a Display can have a different EDID and/or product ID. This is especially true between DisplayPort and HDMI ports which have different capabilities.

The manual says the max resolution for HDMI is 4K (recommended 3840x1080) so the EDID for the HDMI port is probably missing a 5120x1440 timing. I guess you found that the HDMI port can support 5120x1440 (but only 8 bpc RGB because there's not enough bandwidth for RGB 10 bpc) by adding the missing timing. Setting DisplayPixelDimensions property in the override file or setting "Scaled resolution base" in SwitchResX won't help until the timing exists (as it does in the DisplayPort EDID of the display).

The HDMI port also supports 3840x2160 but that's more vertical pixels than real pixels so it might be blurry.

The HDMI port might use YCbCr 4:2:0 (especially for 3840x2160) so you should check with a chroma sub sampling test image.

Chroma Subsampling: 4:4:4 vs 4:2:2 vs 4:2:0

What is Chroma Subsampling and where is this visible? Chroma subsampling is a type of compression that reduces the color information in a signal in favor of luminance data.

www.rtings.com

 

[Rymek]

That's interesing what you're saying. I checked the card on windows when I was fiddling with it, and indeed windows could allow only 4k res using Radeon card on this monitor.

as for 8bit color paletter, i'm using it mostly for programming so don't need 10bit colors anyway, need the screen space

Here's diagnose output.

 

[joevt]

That's interesing what you're saying. I checked the card on windows when I was fiddling with it, and indeed windows could allow only 4k res using Radeon card on this monitor.

as for 8bit color paletter, i'm using it mostly for programming so don't need 10bit colors anyway, need the screen space

Here's diagnose output.

Thanks for the output. As expected, it's identical to the SwitchResX generated override except it doesn't have the DisplayID extension block that SwitchResX created to add the missing 5120x1440 timing for the HDMI EDID.

In Windows, you can use Custom Resolution Utility (CRU) to override the EDID. Just do it like SwitchResX does: Since the resolution is wider than 4096, you need to create a DisplayID extension block, then create a timings block with the 5120x1440 timing (view the timing using the DisplayPort connection first). Click OK to save the changes (click cancel to exit without saving). Run Restart64.exe to force load the changes (so you don't need to restart the computer). Then try the new timing (you may need to quit and launch whatever utility you are using to set the resolution).

Read the instructions at the linked post to see how to undo EDID overrides in Windows.

 

[Rymek]

In windows i'm not using Radeon to drive this display, 2080Ti is doing that (Radeon is disabled in windows). I did that just to check if everything is ok with the card.

Thanks for the help!

 

[joevt]

In windows i'm not using Radeon to drive this display, 2080Ti is doing that (Radeon is disabled in windows). I did that just to check if everything is ok with the card.

Are you saying the Nvidia card can drive the display at 5K using HDMI? I don't think that's likely since the EDID from the HDMI port of the display doesn't have a 5120x1440 timing. In that case, I am saying that you can use CRU to add this missing timing to get 5120x1440 in Windows using HDMI.

 

[Rymek]

Actually 2080Ti is connected through DP

 

[bam2000]

Hi,
i have the exact same Monitor as you, I also enabled all custom Resolutions in the Settings but when I enable 2460x1440 119,88hz in the Menu my Monitor goes black and just flickers once all 30 seconds
Any idea what I can do? I mean I have the exact same Monitor as you and the 3840x2160 with 120hz is working just fine, its just to small, so I would love to have 1440p with high refresh rate scaled to the 4k Resolution...
I hope anyone can help me