LG 31MU97 4K Display not showing 4K on MacPro

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Level 1

13 points

LG 31MU97 4K Display not showing 4K on MacPro

I just bought an LG 31MU97, and plugged the DisplayPort into my MacBook Pro (Retina, 15-inch, Mid 2015), which has an Intel Iris Pro 1536 MB.

Every time I switch the monitor on, I get this message:

I can't seem to do anything within display preferences to get past this:

I know that a similar question has been posed before, but that question was resolved by upgrading to El Capitan. Well, I already have El Capitan. Any ideas what else I could try?

MacBook Pro with Retina display, OS X El Capitan (10.11.6)

Posted on Oct 20, 2016 5:09 PM

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Answer 1

lllaass

Level 10

210,513 points

Oct 21, 2016 1:19 AM in response to unovis

- Try resetting the SMC and NVRAM/PRAM

Intel-based Macs: Resetting the System Management Controller (SMC)

https://support.apple.com/en-us/HT201295

About NVRAM and PRAM

https://support.apple.com/en-us/HT204063

- Try starting in Safe Mode

OS X: What is Safe Boot, Safe Mode?

https://support.apple.com/en-us/HT201262

- Boot to Recovery and repair the startup disk

OS X: About OS X Recovery - Apple Support

https://support.apple.com/en-us/HT201314

This is the Mac Pro desktop forum. I requested your post be moved to the MacBook Pro laptop forum or other appropriate forum.

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Answer 2

unovis Author

Level 1

13 points

Nov 7, 2016 3:11 PM in response to lllaass

Thanks lllaass for your response. I have just tried all of these steps, and nothing has changed. I am still unable to get it to 4096x2160.

Here's what I did:

Reset the SMC, no effect
Reset the NVRAM, no effect
Started in Safe Mode, the resolution problem was the same in there
Booted to recovery mode and repaired the startup disk, no effect

I'm open to more suggestions...

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Answer 3

lllaass

Level 10

210,513 points

Nov 9, 2016 11:19 AM in response to unovis

The Apple specs say for the Iris graphics:

Dual display and video mirroring: Simultaneously supports full native resolution on the built-in display and up to 3840 by 2160 pixels on up to two external displays, both at millions of colors.

If you and the AMD GPU then

Support for up to 5120-by-2880 resolution at 60Hz on a single external display (model with AMD Radeon R9 M370X only)

Thus, you are out of luck getting the native resolution of the monitor to display on your MacBook Pro

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Answer 4

unovis Author

Level 1

13 points

Nov 9, 2016 11:19 AM in response to lllaass

Thanks for your reply. I will take this up with LG support, as they bill this monitor as being Mac-compatible on their site.

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