[SOLVED] Gigabyte HD7970 not displaying at 4K 60Hz over HDMI to Mini Display Port

denno020

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I recently moved house, and when it came to putting my computer together, my monitor will no longer display 4K at 60Hz, displaying at a measly "30 Hertz"

Monitorpng.png


As we can see, I have an AOC 4K monitor, and prior to moving house, I was getting great, super smooth, 4K display.

Prior to moving house, I had 3 monitors set up, 2 x 1080p and 1 x 4K. After the move, I've decided to drop back to a single 4K, which means I have 3 display cords and I don't remember exactly which cord I was using for white monitor prior to the move. I have since found that I can't use my output on the graphcis card, as it only supports 4K up to 30Hz, so I changed to using HDMI cable, plugged into an active HDMI -> Mini display port adapter, which gives me 4K, and sometimes gives me 60 Hertz. I say sometimes because when I go into the Properties in the panel above, and uninstall the driver, then the refresh rate will display 60 Hertz.

Everything seemed to break when I installed the latest Radeon software, and every time I re-install it, the refresh rate always gets reset.

Is anyone able to help with what I'm doing wrong?
 
Solution
To begin, see if this can help

https://www.techspot.com/review/481-amd-radeon-7970/page2.html
AMD reference sample has a dual DL-DVI connector, a single HDMI 1.4a port and two mini-DisplayPort 1.2 sockets.

https://en.wikipedia.org/wiki/HDMI
The AMD Radeon HD 7000 Series implements HDMI 1.4b

None of these (HDMIs) are able to support 4k @60hz BTW.

This is the maximum for HDMI 1.4
3840×2160 24Hz/25Hz/30Hz
4096×2160 24Hz

10.2 Gbps Bandwidth

https://www.quora.com/How-can-I-get-4K-at-60-hertz-in-HDMI-1-4
You can do 4K @24/25/30Hz with HDMI 1.4 but the interface does not provide enough bandwidth for 4K @60Hz. To get enough bandwidth for 4K @60Hz you need HDMI 2.0 or...

Alatrix

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To begin, see if this can help

https://www.techspot.com/review/481-amd-radeon-7970/page2.html
AMD reference sample has a dual DL-DVI connector, a single HDMI 1.4a port and two mini-DisplayPort 1.2 sockets.

https://en.wikipedia.org/wiki/HDMI
The AMD Radeon HD 7000 Series implements HDMI 1.4b

None of these (HDMIs) are able to support 4k @60hz BTW.

This is the maximum for HDMI 1.4
3840×2160 24Hz/25Hz/30Hz
4096×2160 24Hz

10.2 Gbps Bandwidth

https://www.quora.com/How-can-I-get-4K-at-60-hertz-in-HDMI-1-4
You can do 4K @24/25/30Hz with HDMI 1.4 but the interface does not provide enough bandwidth for 4K @60Hz. To get enough bandwidth for 4K @60Hz you need HDMI 2.0 or better.

So, let's take a look at the DP port specs

DP 1.2/1.2aDPmini-DP
Max Link Bandwidth21.6 Gbps21.6 Gbps
Max Payload Bandwidth17.28 Gbps17.28 Gbps
Max Resolution3840 x 2160 (4K) / 60 Hz3840 x 2160 (4K) / 60 Hz

As suggested by this, HDMI 2.0 (and therefore DP 1.2) can hold 4K at @10bit @60hz (the maximum that your monitor supports)
4K-Chart_2.jpg


With this said, there is no way without some kind of compression that you will be able to run @4k 60hz from that HDMI port, but you should be able to do it with the mini-DisplayPort.
The problem is either with the drivers or with the adapter.
Can you please send the model of the adapter?

Edit:
Code:
https://www.reddit.com/r/Monitors/comments/eh75x9/new_monitor_has_refreshrate_60_hz_and_8_bit_color/
[url=https://www.techspot.com/review/481-amd-radeon-7970/page2.html]https://www.techspot.com/review/481-amd-radeon-7970/page2.html[/url]
https://www.startpage.com/row/search?q=HDMI+Adopter+extranet.&l=english
https://levvvel.com/displayport-vs-mini-displayport/
http://www.innomind.org/hdmi-1-4-specifications/
https://www.startpage.com/row/search?q=4k+60hz+minimum+bandwidth&l=english


(Would appreciate if you could like the answer since I spent way too much time in writing this ♥)

Bye
 
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Solution

denno020

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Thank you so much for that detailed answer Alatrix! Absolutely I will like it ❤

As for the adapter, it is this one here.

I do worry that it's the drivers that are causing issues, and I've tried downloading all sorts of combinations, tried relying on Windows Update to find the best drivers (it continually telling me that the best drivers were installed, no matter what was or wasn't installed), and I've attempted installing multiple versions of the Radeon software, hoping that I would find one that might "fix" my problem..

In case it's helpful, here is the Adapter tab details:

Adapter.png
 
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Alatrix

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Look at what I found!
This could be the solution for your problem:
I'm not sure it is the exact model of your monitor, but I think it is.

https://us.aoc.com/en/monitors/u2790vq

Connections
Signal inputHDMI 1.4 x 1, HDMI 2.0 x 1, DisplayPort 1.2 x 1, VGA
Displayport Version 1.2

This means that your monitor has a DP 1.2 (@4K 60hz), an HDMI 2.0 (@4K 60hz) and an HDMI 1.4 (@4K 30hz)
The issue might just be that you are using the wrong port on your monitor.

In your monitor's (not sure if it is the right model tho) manual, I found this:
Optimal preset resolution3840x2160@30Hz(HDMI2)
3840x2160@60Hz(HDMI1、DP)

The adapter should be fine (and it comes with lifetime warranty, so, no problem here), the issue at this point could be with drivers, you might be using the wrong port on the monitor, or it might be the cable itself (maybe it's an HDMI 1.4).
In any case, a new cable like this, that goes without an adapter should fix any issue.

Sorry for the bad English
Bye
 
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denno020

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Thanks Alatrix, that certainly looks a lot like my monitor.
I'm definitely using HDMI 1 already though, so it seems that isn't the problem.
I've got my tower a couple of metres away from my monitor - I've been looking for a longer display port to mini display port, but haven't yet been able to find one.

I really think the drivers are the issue, but I can't figure out the combination to install to get it to recognize 60 Hz, and to be honest I really feel like the AMD software has done more harm than good.

Also, opening up the monitor details, it says that I'm getting 65KHz horizontally, but 30 Hz vertically.. I'm not sure what the difference is, or why they'd be different..
 
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denno020

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Something else that might be of interest, these are the modes that I've got available:
Modes.png


Then, when I close this "List All Modes" panel, then click on Properties for Adapter and choose to uninstall the driver, I get the following modes:

Modes2.png
 

Alatrix

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Ehm?
But still

I have had so many problems with amd drivers but the new really fixed a good amount for me.

To begin, make sure that the hdmi cable is 2.0 and not any lower version.

IMO you should buy the cable I linked above and if it still somehow didn't work, just send it back maybe and you will know for sure that is a driver issue

I don't have a magic to fix your drivers, so I can't help you here.

I have no idea of what 65KHz means.
Ps.: please fix my name in your reply, please
 

Alatrix

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Something else that might be of interest, these are the modes that I've got available:
Modes.png


Then, when I close this "List All Modes" panel, then click on Properties for Adapter and choose to uninstall the driver, I get the following modes:

Modes2.png
Does that mean that you can run 60hz on the basic display adapter?
 

denno020

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Even when I go to the manufacturers website and download the drivers, then tell WIndows that I have them on my disk, selecting the ones downloaded from the manufacturer, I get told this
AOC-Drivers.png
 

Alatrix

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denno020
I doubt you were actually using 4k 60Hz before you moved and were likely either using 1080p or 1440p at 60Hz or even possibly 4k at 30hz. Just get a Displayport cable and stop trying to use HDMI on your GPU, because the HD 7970 isn't capable of 4k 60Hz output through HDMI.
He is not trying to output @4k 60hz trough HDMI, he is using the mini-DP and converting into HDMI
 
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He is not trying to output @4k 60hz trough HDMI, he is using the mini-DP and converting into HDMI
Oh, that is my mistake. I had been looking at another post and walked away and got myself all confused when I came back and started writing my response. Whoops! :giggle:

After having another read through I see you suggested the OP just get a Mini-DP to DP cable instead of trying to use an adapter to HDMI which would be the best option. A custom resolution in the Radeon settings menu might make the Mini-DP to HDMI active adapter work.
 
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denno020

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@Alatrix , you have been an absolute trooper, thank you so much for your continued help!

Thank you also to @Third-Eye. I tried the custom resolution suggestion in the Radeon settings (after actually looking up how to do it properly this time), and wouldn't you know it, it appears to be working again! 4k @60Hz

All-Modes.png


Again, thank you so much for your continued help @Alatrix
 

Alatrix

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@Alatrix , you have been an absolute trooper, thank you so much for your continued help!

Thank you also to @Third-Eye. I tried the custom resolution suggestion in the Radeon settings (after actually looking up how to do it properly this time), and wouldn't you know it, it appears to be working again! 4k @60Hz

All-Modes.png


Again, thank you so much for your continued help @Alatrix
Happy it worked, I would have never guessed.
It has been nice to talk to you and see you around.

Ps.: mark the thread as solved

Bye