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Custom Resolution Utility (CRU)
05-19-2022, 09:30 PM
Post: #6611
RE: Custom Resolution Utility (CRU)
(05-19-2022 01:05 PM)dutch45612 Wrote:  There are many option in that software that i don't really know about and maybe there is something i overlooked that could makes the thing works for me... I would be really grateful if someone could give me a clue, any piece of info would be welcome Smile.

The device is a GPD WIN 3, with an integrated Intel Iris graphic and a "digital flat panel" by the device manager drivers...
Intel's driver does not allow custom resolutions or EDID overrides with some internal displays.
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05-19-2022, 09:30 PM
Post: #6612
RE: Custom Resolution Utility (CRU)
(05-19-2022 04:59 PM)ROYER_XIV Wrote:  I recently encountered problems with my AMD card, this story of VRAM frequency too high while idle.
That led me here, and to the discovery of CRU.
However, I have two questions:
- the maximum pixel clock of my monitor is 330. If I choose CVT-RB, I get 346. If I choose CVT-RB2, I get 332.
Is it better to choose CVT-RB2, and block the pixel clock at 330 (and thus go from 144hz to 142hz) or to choose CVT-RB, even though the pixel clock exceeds that of my monitor?

- Can changing all this cause changes in the display? I know that if we switch to CVT-RB via the AMD software, the colors are degraded for example.
You're leaving out a lot of information. What video card? What monitor? What connection: DVI, HDMI, DisplayPort? What resolution? I'm assuming 1920x1080. How are you determining the maximum pixel clock? The timing parameters should not affect the visible image. How are the colors degraded?
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05-19-2022, 10:36 PM (Last edited: 05-19-2022, 10:39 PM by ROYER_XIV)
Post: #6613
RE: Custom Resolution Utility (CRU)
(05-19-2022 09:30 PM)ToastyX Wrote:  
(05-19-2022 04:59 PM)ROYER_XIV Wrote:  I recently encountered problems with my AMD card, this story of VRAM frequency too high while idle.
That led me here, and to the discovery of CRU.
However, I have two questions:
- the maximum pixel clock of my monitor is 330. If I choose CVT-RB, I get 346. If I choose CVT-RB2, I get 332.
Is it better to choose CVT-RB2, and block the pixel clock at 330 (and thus go from 144hz to 142hz) or to choose CVT-RB, even though the pixel clock exceeds that of my monitor?

- Can changing all this cause changes in the display? I know that if we switch to CVT-RB via the AMD software, the colors are degraded for example.
You're leaving out a lot of information. What video card? What monitor? What connection: DVI, HDMI, DisplayPort? What resolution? I'm assuming 1920x1080. How are you determining the maximum pixel clock? The timing parameters should not affect the visible image. How are the colors degraded?

I have a rx6800, 144hz 1080p monitor ( AOC 24G2U, displayport) and 60hz 1080p monitor (BenQ GW2480, hdmi).
I saw the maximum pixel clock of my monitor in CRU, where you can check the monitors informations.
I tested both cvt-rb and cvt-rb2, and both of them make the VRAM frequency go down to an acceptable level.
My question is: is it better to choose CVT-RB, and exceed the pixel clock of my monitor, or CVT-RB2 which is almost the same pixel clock of my monitor ?

My monitor pixel clock : 330
CVT-RB pixel clock : 346
CVT-RB2 pixel clock : 332

I can cap the hertz to 142, to stay at 330 pixel clock with CVT-RB2.

The colors are degraded with the AMD software, because it's decreasing from 8 bits to 6 bits, I dont know why.
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05-19-2022, 11:18 PM
Post: #6614
RE: Custom Resolution Utility (CRU)
(05-19-2022 10:36 PM)ROYER_XIV Wrote:  I have a rx6800, 144hz 1080p monitor ( AOC 24G2U, displayport) and 60hz 1080p monitor (BenQ GW2480, hdmi).
I saw the maximum pixel clock of my monitor in CRU, where you can check the monitors informations.
I tested both cvt-rb and cvt-rb2, and both of them make the VRAM frequency go down to an acceptable level.
My question is: is it better to choose CVT-RB, and exceed the pixel clock of my monitor, or CVT-RB2 which is almost the same pixel clock of my monitor ?
The limit reported by the monitor is not important. The monitor probably uses DisplayPort HBR mode with 4 lanes, which supports up to 360 MHz pixel clock at 8 bpc, so you can use either CVT-RB or CVT-RB2 at 144 Hz without a problem. If CVT-RB2 works fine, use that. If you exceed 360 MHz, the color depth will automatically drop down to 6 bpc, so if that's happening when using CVT-RB with AMD's software even though the pixel clock should be below that point, then it must be a driver bug.
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05-20-2022, 03:51 AM
Post: #6615
RE: Custom Resolution Utility (CRU)
(05-19-2022 09:27 PM)ToastyX Wrote:  I don't know the capabilities of that chip. I saw a reply on reddit that says the Synaptics VMM7100 doesn't support VRR. Parade supposedly has a chip that does VRR (PS 196), but I don't know what uses it.

It does appear that this chip isn't able to support VRR. I'll have to look out for an adapter that does use ps196. Thanks.
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05-20-2022, 08:33 AM
Post: #6616
RE: Custom Resolution Utility (CRU)
(05-19-2022 11:18 PM)ToastyX Wrote:  
(05-19-2022 10:36 PM)ROYER_XIV Wrote:  I have a rx6800, 144hz 1080p monitor ( AOC 24G2U, displayport) and 60hz 1080p monitor (BenQ GW2480, hdmi).
I saw the maximum pixel clock of my monitor in CRU, where you can check the monitors informations.
I tested both cvt-rb and cvt-rb2, and both of them make the VRAM frequency go down to an acceptable level.
My question is: is it better to choose CVT-RB, and exceed the pixel clock of my monitor, or CVT-RB2 which is almost the same pixel clock of my monitor ?
The limit reported by the monitor is not important. The monitor probably uses DisplayPort HBR mode with 4 lanes, which supports up to 360 MHz pixel clock at 8 bpc, so you can use either CVT-RB or CVT-RB2 at 144 Hz without a problem. If CVT-RB2 works fine, use that. If you exceed 360 MHz, the color depth will automatically drop down to 6 bpc, so if that's happening when using CVT-RB with AMD's software even though the pixel clock should be below that point, then it must be a driver bug.

Okay, thank you very much for the information
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05-23-2022, 11:40 AM
Post: #6617
RE: Custom Resolution Utility (CRU)
Hi there,

I was hoping to get some help. I have tried a few different tutorials posted online and on forums, but I have been unsuccessful in adding 1440x1080 @ 390hz as a custom resolution. I have the following:
  • Acer AOPEN Fire Legend 25XV2Q 390hz monitor
  • GIGABYTE AORUS GeForce RTX 3080 XTREME
  • KabelDirekt 10ft DisplayPort, DP 1.4, VESA-Certified
  • Windows 10 21H2

Someone posted this video (https://www.youtube.com/watch?v=IZEM6Qhw0N0) of them applying this custom resolution to their Acer Nitro 390Hz which is supposedly the same panel.

I don't know if that is even the best way to force display scaling at those resolutions for a refresh rate as high as 390hz. I have been able to create a custom resolution of 1440x1080 in the Nvidia control panel, which I believe creates the resolution and timings at 60hz and then GPU scales (I could definitely be wrong). However, it deletes itself after I restart my PC so it isn't much of an alternative. Maybe that will give some insight as to what is going on with everything. Thanks in advance! Smile
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05-23-2022, 01:57 PM
Post: #6618
RE: Custom Resolution Utility (CRU)
(05-23-2022 11:40 AM)carbs Wrote:  I was hoping to get some help. I have tried a few different tutorials posted online and on forums, but I have been unsuccessful in adding 1440x1080 @ 390hz as a custom resolution.
Unsuccessful how? What happens?
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05-25-2022, 04:54 AM
Post: #6619
RE: Custom Resolution Utility (CRU)
(05-23-2022 01:57 PM)ToastyX Wrote:  
(05-23-2022 11:40 AM)carbs Wrote:  I was hoping to get some help. I have tried a few different tutorials posted online and on forums, but I have been unsuccessful in adding 1440x1080 @ 390hz as a custom resolution.
Unsuccessful how? What happens?

The res just doesn't appear as a possible mode. No errors or anything. Just doesn't show up in the list.
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05-25-2022, 02:55 PM
Post: #6620
RE: Custom Resolution Utility (CRU)
(05-25-2022 04:54 AM)carbs Wrote:  The res just doesn't appear as a possible mode. No errors or anything. Just doesn't show up in the list.
Then you'll have to show me exactly what you're doing. Export a file with the changes and post it here.
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