Macbook Pro aspect ratio issues with LG 27UK850 monitor

Look at the LG setting for Ratio.

The choices should be WIDE/ORIGINAL/1:1

You want 1:1

There my be different setting for different inputs (USB-C, HDMI).

Are you using display mirroring? That could change display size to match the MacBook Pros' s 2560-by-1600 to the LG's 3840x2160.

purinahall Said:

"Hey, thanks for replying. I did, but check out what I also said on my inquiry: 'I looked at the underscan/overscan documentation, however my Macbook does not show me the slider as well as it won't show me specific resolutions, I believe all Display options have changed on Catalina.'"

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Two Thoughts:

Reset your SMC and Your NVRAM.

• How to reset the System Management Controller (SMC) on your Mac - Apple Support
• Reset NVRAM or PRAM on your Mac - Apple Support

Changes Occur, and sometimes your Mac needs to reset itself. as a way to get back to its default operations.

Try a USB-C to DisplayPort Cable.

https://www.startech.com/AV/display-and-video-adapters/usb-c-video-adapters/usb-c-displayport~CDP2DPMM1MW

It won't provide charging power, but should give full 60Hz refresh rate.

purinahall Said:

"Macbook Pro aspect ratio issues with LG 27UK850 monitor: I'd say I found a way to "hack" it, but it definitely should not be the correct solution to it. The ONLY way that I could get no bars and a good resolution (no blurry fonts) is when I connected my 2018 MBP to the monitor in two ways. [...]I don't know why this works at all, but it's the only way to get the result I want, so I've just gone with it. It's insane though... Just thought I'd leave it out here in case someone runs into this but it seems like a one-of scenario"

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Amperage/Voltage is 1:1:

It is probably working because of Amperage/Voltage Aspect Ratio equalling out 1:1

So, Three Thoughts...

A. Reply to this Thread with Info:

Providing in 3 bullets the links to the adapters you use and with what type of cable.

• Adapter 1 & How to Use It
• Adapter 1 & How to Use It
• Adapter 1 & How to Use It

B. Inform Apple of your Solution:

Also, inform Apple of this your success using their Apple Feedback Forum:

1. Go Here: Feedback - MacBook Pro - Apple
2. Select: "Software/Hardware Compatibility" for the "Feedback Type"
3. Proceed from there as necessary.

C. My 30" Apple Cinema Display - to - Mac's HDMI (Amperage/Voltage Aspect Ratio Equalling Out 1:1):

Also Amazon seems and adapter that I use, and it is highly recommend on these forums for newer MacBooks used with older monitors. In my case, I use the USB-C to Mini DisplayPort Adapter 4K@60Hz - Silver and from that I connect the Belkin 4K Mini DisplayPort to HDMI Adapter. That has worked for many when using the 30" Apple Cinema Display with their Mac. So, I wonder if that would work, despite it no being the 30" Apple Cinema Display?

purinahall Said:

"Macbook Pro aspect ratio issues with LG 27UK850 monitor: [...] as you can see on the image attached I can't seem to figure out how to get rid of those black bars around the screen (I believe it's called Underscan) and I'd like to leverage the full display.[...]"

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Go Here: About Overscan and Underscan on your Mac, Apple TV, or Other

purinahall Said:

"Macbook Pro aspect ratio issues with LG 27UK850 monitor: [...]It's weird to me that when I tried an old HDMI cable with an old USB-C dongle it showed lower and limited resolution options but it got rid of the black bars and did show full screen (again, even with undesired resolutions). [...]Any suggestions? (I bought that adapter because I'm currently not located in the States and that's the best cable I could find out here)."

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Thank you for the followup.

A couple of thoughts:

1. Try all the resolutions shown - see what resolution makes these disappear.

2. Contact LG:

eMail them here: comm.display@lge.com. In the eMail, them a few questions, such as:

• Why do I get these Bars?
• How do I make them disappear
• Is my TV 4K-compatible
• Can I get High-Definition without the Bars?

Perhaps this is a Faulty Device:

The USB adapter would play no part in this, unless it were faulty. In that case, return it to the store where you go it.

And a Monster Cable is unnecessary - using a chinsy one would do just fine.

What I Use:

As for the adapter to get, this is what I use on my 4K projector: USB-C Digital AV Multiport Adapter. It has a HDMI port for my TV & Projector, a USB-C port for charging your Mac; and a USB-A port for another connection. I use the slim plug that came with my 4K projector. Its chinsy, but does the job.

purinahall Said:

"Hey, thanks for replying, that's a good suggestion. I just wonder how sure I can be that this will work before spending an extra $50 or so you know?"

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I Use it & it Gets the Job Done:

As I mentioned above, that is what I use with my TV & 4K projector, and works just fine.