4k TV LG 70UK6500PLB with MacBook Pro 2012

is it possible to use a 4k TV with a MacBook Pro 2012?

yes, but…

the 15″ MacBook Pro 2012 has two GPUs:

  1. an Intel HD Graphics 4000
  2. and an NVIDIA GeForce GT 650 MB

We used a 4k Moshi mini DisplayPort to HDMI adapter to connect the TV with an appropriate cable in order to get sound output too.

By default you will get a native resolution of 3840 x 2160 at 30Hz. It’s ok for general use, however when watching a movie the side-effect of slow refresh rate becomes disturbing.

If the only purpose of connecting the TV is to watch 720p or 1080p movies, then why not lower the resolution in order to get higher refresh rate?

Going to Apple / System Preferences / Display choosing the second option gives a 1920 x 1080 pixel resolution but again at a 30 Hz refresh rate. You can check this by going to Apple / About This Mac… System Report… Graphics/Display…

Seams like Apple’s programmers have not put enough intelligence into the switching mechanism as this GPU support a way higher refresh rate than 30 Hz at Full HD.

In order to unleash the power of this GPU we need a third-party app like SwitchResX.

The app allows the use of 1920 x 1080 at 100 or even 120 Hz.

A quick check at Apple / About This Mac… System Report… Graphics/Display… shows that it’s really 120 Hz. You might however use the lower 100 Hz setting as it’s more than enough for any movie.

read more about refresh rates here