Dell up3216q 4k monitor can only output 30hz

[Grolubao]

Hello all,

I've updated to OsX Catalina and it seems the refresh rate of my external monitor went from 60hz to 30hz which is quite annoying.

Did anyone experience the same?

Cheers

 

[ruslan120]

Can’t chime in with regards to experience but you can set resolution and refresh rates using SwitchResX.

Regrettably, it’s shareware. Like $15-$20.

 

[CC88]

Hi. I own an LG 32UD59-B that works in 60Hz but it show some glitch when I scroll down the menu. It doesn't show any problem in 30Hz...

With High Sierra no problem at all.

 

[Hessel89]

I had this exact monitor and it can perfectly display 4K @ 60hz.
If you're running it over HDMI, you need to go into settings (can't remember where exactly) and change HDMI 1.2 into HDMI 2.0. Making sure you're actually using HDMI 2.0 cables ofcourse. Same goes for Displayport. You need 1.2 at least.

 

[CC88]

I had this exact monitor and it can perfectly display 4K @ 60hz.
If you're running it over HDMI, you need to go into settings (can't remember where exactly) and change HDMI 1.2 into HDMI 2.0. Making sure you're actually using HDMI 2.0 cables ofcourse. Same goes for Displayport. You need 1.2 at least.

If you are talking about LG 32UD59-B I have both DisplayPort 1.2 and HDMI 2.0 set. I think the problem is something with Catalina and Mojave because I have no problem at all in High Sierra using it 4K@60Hz.

But I have some glitch in Mojave and in Catalina too. I own a nMP6.1 and use the monitor via miniDp to Dp cable. I have also changed cables etc. but I can't solve. The only way to not show glitch during finder menu scrolling is using it at 30Hz.

 

[Hessel89]

If you are talking about LG 32UD59-B

The Dell UP3216Q. Works fine in Mojave.

 

[CC88]

The Dell UP3216Q. Works fine in Mojave.

Thanks a lot for your feedback.

Also my LG works fine in High Sierra but not in Mojave and Catalina.

Ordered a new 32" form Benq... I will see what happen then.

 

[shinji]

I have the same problem on a Dell P2415Q connected HDMI->HDMI on a 2018 Mac Mini. I had changed the setting previously to enable 60hz, and it was working fine. After Catalina's supplemental update, I'm only getting 30hz no matter what I do. It was actually working fine in Catalina before yesterday's update.

There are some other reports of this I've found from Googling, too.

 

[syawaworht]

Got 60hz back: https://www.reddit.com/r/MacOSBeta/comments/csm5r9/_/f33vden
In Displays, switch back and forth between "Default for Display" and "Scaled" (Doing this fixed the problem for me today)