Why does my mac mini show only 30, 25, 24 refresh rates?

[Cape Dave]

I am quite sure my monitor, a Dell 4k P2715Q, will do 60hz. Holding the Option Key and clicking "scaled" does nothing. Thank much, I am thinking I may need a different cable? I have a nice HDMI cable.

 

[vddobrev]

I have the same monitor, follow this guide to enable 4K@60Hz

Setting Up the P2415Q and P2715Q Monitors with HDMI 2.0 that Support 4K x 2K 60Hz | Dell Bulgaria

 

[Amethyst1]

Yep, HDMI 2.0 has to be enabled manually.
If your monitor was built before the cut-off date mentioned in the article it’s limited to HDMI 1.4 (30 Hz) though. (If you have an Intel Mac you can get 38 or 39 Hz using custom timings in this case.)

 

[vddobrev]

Alternatively, use DP or mDP cable.

 

[Cape Dave]

Alternatively, use DP or mDP cable.

Copy that, thanks. I must have one of those around somewhere

 

[Cape Dave]

I have the same monitor, follow this guide to enable 4K@60Hz

Setting Up the P2415Q and P2715Q Monitors with HDMI 2.0 that Support 4K x 2K 60Hz | Dell Bulgaria

This worked great, much thanks.

 

[Cape Dave]

Well, no rest for the wicked. I have horrible flickering where it just goes blank for a few seconds every minute or so. Ouch. I have ordered a USB-C to Display port cable.

 

[Amethyst1]

Well, no rest for the wicked. I have horrible flickering where it just goes blank for a few seconds ever minute or so. Ouch.

Forget HDMI. Try DisplayPort.

 

[Cape Dave]

Forget HDMI. Try DisplayPort.

Yeah, my cable comes Friday. USB-C on the mini to Display Port on the monitor

 

[Cape Dave]

Thank you, thank you! I got the display cable today and installed it and 60hz! No flickers! Awesome!