Custom Resolution Utility (CRU)

[GroovyMotion]

Greetings,
just found this forum while doing searches for my issue!

I did try CRU, added a custom res of 1080p 60hz and my TV still displays 1080p 24hz.

In Win10, it detects both my monitor and TV and both only get the option to select 60hz (Display settings -­> Monitors).
My issue is, when I am on the desktop or within a browser, I can only get 24hz on the TV but once I am inside any games, then it switches to 1080p 60hz!

It seems that the signal sent to my TV via my Denon amp is not registered properly.
I have a GTX 970 with a HDMI 2.0 cable.
So, like I said it is only outside games that it gets stuck to 24hz. Even fullscreen YT videos are stuck at 24hz, which is quite annoying!

Any help would be greatly appreciated!

Cheers!

[Amstellodamois]

Hello there!

I was wondering....would this utility allow me to force a resolution on a headless system?

Alas, when I TeamViewer into my system with no monitor plugged in, I'm forced to use 640x480...which isn't very practical.

[ToastyX]

(01-24-2018 09:30 AM)Amstellodamois Wrote:  I was wondering....would this utility allow me to force a resolution on a headless system?

No, CRU deals with physical monitors. Someone said this though:

(10-05-2017 04:16 PM)tolisss Wrote:  actually i remote connect to this machine with teamviewer without having a monitor, like so windows does not detect any monitor. The cru failed to start only on one machine but worked on another. However after your answer i connect a monitor for just one boot and cru started again! I was able to add custom resolution that worked even if monitor is not attached to the system.

[ToastyX]

(01-23-2018 08:45 PM)GroovyMotion Wrote:  I did try CRU, added a custom res of 1080p 60hz and my TV still displays 1080p 24hz.

In Win10, it detects both my monitor and TV and both only get the option to select 60hz (Display settings -­> Monitors).

If the only option is 60 Hz, then the video card is sending 60 Hz. How do you know it's displaying 24 Hz? I haven't heard of a situation where the desktop runs at the wrong refresh rate while games don't. It's usually the other way around.

[GroovyMotion]

(01-24-2018 11:16 AM)ToastyX Wrote:  

(01-23-2018 08:45 PM)GroovyMotion Wrote:  I did try CRU, added a custom res of 1080p 60hz and my TV still displays 1080p 24hz.

In Win10, it detects both my monitor and TV and both only get the option to select 60hz (Display settings -­> Monitors).

If the only option is 60 Hz, then the video card is sending 60 Hz. How do you know it's displaying 24 Hz? I haven't heard of a situation where the desktop runs at the wrong refresh rate while games don't. It's usually the other way around.

It shows 60hz in Windows and 24hz on my tv so there is something wrong.
The issue might be my Denon sice I plugged my laptop directly to the TV and it works fine at 60hz.
But still, why would the issue happens when I am using my desktop PC and being outside a game.

[alexis20ro]

knowing somewhone resolution code 2560 1440 from 0 to 255 the 255 is 4k cru hdmi link.

[fandangos]

Hey Toasty,

I'm trying to add custom resolutions to my hdmi 1.4 4k display with chroma 4:2:0.

I would like to add 3200x1800 and 2560x1600 but with chroma reduced to be able to fit on the limited bandwidth of hdmi 1.4.
The thing is when I go into detailed resolutions it asks for a resolution code, a hex from 0 to 255.

Is there a list for those values available?

[ToastyX]

CRU already includes all the useful resolutions. YCbCr 4:2:0 only works with 3840/4096x2160. There are no codes for 3200x1800 or 2560x1600/1440.

[CRTFTW]

So it's been recently discovered that there is a specific type of displayport splitter that includes a DAC that is capable of 550+ mHz pixel clocks. The IC making this possible is manufactured by Synaptics. This is the version of the adapter I have:

http://www.sunix.com/product/DPU3000.html

It runs off the displayport 1.2 spec, and as long as you only use its VGA output, it can hit very high pixel clocks. I'm still unsure where the ceiling is precisely. So needless to say this is the DAC CRT users have been waiting for, allowing us to use the full range of our monitors on newer GPU's that don't have analog out.

Anyway, I've run into a strange problem where Radeon GPU's on Windows PC's are running into artificial resolution limits in the driver, and they're ignoring overrides above this limit in CRU, and enforcing the same limit in AMD custom resolution tool. Basically, it seems to be looking at the max resolution or pixel clock on the EDID, and limiting the custom resolutions to near that maximum. Resolutions from CRU just won't show up, they're ignored and not selectable

Like when I hook up a Dell P992 (max resolution on EDID is 1600x1200@85hz, max horizontal scan 107kHz) I can't pick resolutions much higher than 2048x1536. But when I use my larger LaCie monitor, where 2048x1536@85hz is the max in the EDID, I can create resolutions with horizontal width around 2700 pixels, like 2736x2054@60hz.

These limits are not present on the actual GPU's VGA output. So for example, on both my Dell and LaCie monitor, I can create a 2880x1620 resolution, and it will display as long as it is within the monitor's range. This resolution, at any usable refresh rate, isn't possible running through the Sunix.

So it's clearly some sort of limitation the driver enforces on displayport when it reads the EDID, and it can't be overwritten. I should mention this is with Radeon+Windows+displayport specificially, another user tested the adapter in Ubuntu and didn't hit any driver-enforced roadblocks.

So what I did is I bought a spoof HMDI 2.0 plug with a 4k60 EDID, and ran it through an Extron switch where the DDC signals were pulled from the HDMI plug, but the RGBHV signals still made it to my actual monitor. My GPU read the spoof's EDID, but for some reason was limited to 2560x1600@60hz, much lower than some of the resolutions/refresh when I hooked up my LaCie to the Sunix.

So I was wondering if you could take a look at the two attached pictures of the EDID's. One is the LaCie, the other the dummy plug, and see if maybe you can tell why the 4k dummy plug isn't unlocking much higher resolutions options than the LaCie, considering the dummy plug has 4k60 in its EDID. Both of these are the EDID's read from the DDC lines, unaltered by me.

My best guess at the moment is that the 4k resolutions are all contained in the extension block, and thus are looked over by Radeon's drivers.

[wood1y]

Hi ToastyX,

Do you think it is possible to run 3440x1440@100Hz on Dual-link DVI?
(The manual lists it as possible (see image), also here says that the limit can be more than 330hz for DDVI, but I couldn't get it to work.)

(I can get 3440@100hz on DP, but I have 2 computers connected to the monitor and I want both running on 100hz without switching cables all the time)

I patched the driver, tried adding the resolution with CRU but when I select I get black screen.