CAC – 1170 and Macbook Pro Retina 2015 not working at 60Hz

Updated on 01-03-2016 in Adapters and Cables
1 on 29-02-2016

My CAC- 1170 just arrived. Very disappointed to discover it will not run at 3840 x 2160 at 60 Hz. Runs 30 Hz OK – but so does every other mini display port to HDMI adapter. Can anybody help with advice ?


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0 on 01-03-2016

Hi Vertullo,

Here’s my standard checklist (not all points will be applicable for you) …

* Color Depth (often default set to 16 bits or even 32 bits) need to be set to 8 bits (when running 4:4:4) or 12Bit when running in 4:2:2. I am quite sure the adapter does not support higher color depth than 12bit.

* Make sure the HDMI port your using on the TV is HDMI 2.0 capable or 3840x2160p 60HZ capable. Often TV’s have like 4 HDMI ports, but only 1 is suited for “2.0” standard.

* Make sure the HDMI cable you are using can do HDMI2.0 or 18Gbps.

* On many TV’s you need to turn on “UHD Color” manually in the settings of your TV for the HDMI port to which your pc is connected.

* Also it could help when connecting 2 screens, to set the screen connected thru the Adapter as second/secondary screen

* When choosing a custom resolution please select for Timing Standard “CVT-RB” (reduced blanking)

I do have some end-user feedback that needed to make custom resolutions with ResSwitchX for instance …

Verified Purchase

I’m using this to successfully send a 3840×2160 60hz signal via my late 2013 Mac Pro with dual AMD Firepro D500 video cards. The normal display settings would not allow me to select 60hz as a refresh rate, but after I installed SwitchResX and created a 4k monitor profile with a 60hz vertical frequency, I was able to simply select the new settings and it works fine. It’s a more involved process using El Capitan to set up a custom profile, but it can be done if you look up some of the other reviews here or on SwitchResX’s website.

Hope it helps

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