I’d like to share how I was able to get my Mac laptop to work at 4K 60 hz with the Vizio M series TV, which has been notoriously difficult to get to play nice.
I have a 2014 15″ Macbook Pro Nvidia 750M 2 GB and a Vizio M50-C1.
Step 1: Install latest firmware update for CAC-1170 adapter. Email [email protected] to get the latest firmware.
Since the firmware installer is an .exe (Windows only), you need to use a Windows laptop with a AMD, Nvidia, or Intel graphics card to install the firmware on the adapter. I borrowed a friends laptop with a Nvidia GTX970M card to install this firmware. Follow the instructions in the email from [email protected].
Step 2: Once the firmware is the ps176b0_0x07.0x00.0x23 version, install SwitchResX on Mac OS X (http://www.madrau.com).
1. Follow instructions to disable System Integrity Protection (SIP) so that u can install a custom resolution.
2. Create a custom resolution of 3840 x 2160 at 60 Hz using the Preset “CVT-RB” and simply putting the vertical “scan rate” as 60 hz.
3. Save this custom resolution
4. Restart computer to install custom resolution
Step 3: Once restarted, check in SwitchResX preferences to see if the custom resolution has been installed. If so, connect Macbook Pro to the M50-C1 (or other M series) to HDMI Port 5 using the CAC- 1170 and HDMI cable (18Gbps capable). Use SwitchResX to change the resolution to either 1080p @ 60Hz (HIDPI aka Pixel doubled) or 3840 x 2160 @ 60 hz (native res). Hold your breath and it should let you finally use your Vizio M series at 4k 60hz. Check refresh rate by using the UFO test (www.testufo.com/#test=framerates)