MacMini and LG 34UM95 causing black borders around screen

Hi all,

So I am having issues with a new setup ..

New Mac Mini (mid-level late 2014 model)
New LG 34UM95 Dislpay
Thunderbolt 2 connection
Yosemite (latest updates)

The mini shows a resolution of 3440x1440 but there are black borders around the screen - like underscan.

I don't see an option to adjust the scan under Prefs->Display ..

I tried to connect a MBP 2012 to the monitor to troubleshoot and it works as intended, no black borders.

Has anyone experienced that same? Am I missing something?

Thanks in advance.

Looking at the image in your post. It looks like your selecting a "scaled" resolution for the display. What happens if you choose the "Default for Display" option?

This is generally the resolution that looks best.

- Nick

Also. According to the specs for a 2014 Mac-mini. Maximum supported resolution is 2560x1600. If choosing a resolution greater than this (3440x1440)…my guess is the computer/monitor setup is "filling in" the unsupported area with the black border.

- Nick

No difference ..with choosing Default for Display option.

I've tried Thunderbolt and HDMI connections as well.

I have seen videos and comments of people powering the monitor with a 2014 Mac Mini without any issues. 3440x1440 at 50Hz.

And yet another thought. If this 2012 MacBook Pro that was used is a retina display model…this is a totally different "ballgame".

- Nick

Examples:

Mini 2014 w the same monitor ..

Video (in German unfortunately)

https://www.youtube.com/watch?v=O1BjF8yp7Xg

Comment from Amazon ..

3) I have recently purchased a current Mac Mini and can say that the Mini, through Thunderbolt, DOES push this resolution 100% BUT at 50Hz. I can rarely see some hesitation when opening windows through the Mini because of the lack of descrete graphics but that's it. The Mini does just fine. It even pushes some older games at full res without any tearing or screen jitters. If you have a 2012 or later Mini (Intel graphics 4000), this display will work at full res but at 50Hz.

Bytestream said:

I have seen videos and comments of people powering the monitor with a 2014 Mac Mini without any issues. 3440x1440 at 50Hz.

Click to expand...

Can you post a link or links to this info? I would like to see what's going on with these people's setups. Maybe there's something going on that hasn't been mentioned.

- Nick

pigoo3 said:

And yet another thought. If this 2012 MacBook Pro that was used is a retina display model…this is a totally different "ballgame".

- Nick

Click to expand...

It is a Retna .. and your point is understood .. the reason I tried the MBP was to see if it was a monitor problem (would the monitor act the same with both connected).

But .. the videos clearly show it working correctly.

Bytestream said:

But .. the videos clearly show it working correctly.

Click to expand...

I've been doing some internet searches on this…and I found this:

Lost my 4K resolution on my Mac Mini with Mac OS X Yosemite | NAS Storage Blog

The "Update" at the bottom of the article is the important part. And says this:

"UPDATE:
Finally fixed this. After the whole patching circus i found a little trick for display more resolution options. Go to System Preferences in Yosemite -> Displays -> Display tab. Hold down option + left mouse click on Scaled. BOOM! Now the 3440 x 1440 resolution could be selected."

HTH,

- Nick

I will give that a try .. but that issue I believe had to do with people that had the monitor working correctly with Mavericks then when they upgraded to Yosemite, they lost the ability to select 3440x1440 .. (Apple pulled that choice for some reason). Since then Apple has patched Yosemite to allow you to select that resolution ..

For my Mini - it has the latest updates and allows me to select the 3440x1400 res without the need to patch it.

Yet the black borders ..

From a technical perspective .. what am I seeing with the black borders? The image is crisp and sharp yet does not fill the screen (I don't expect it to be any sharper honestly) .. is it lacking resolution? is it underscanning?

Bytestream said:

I will give that a try .. but that issue I believe had to do with people that had the monitor working correctly with Mavericks then when they upgraded to Yosemite, they lost the ability to select 3440x1440 .. (Apple pulled that choice for some reason).

Click to expand...

If you read the article in the link I provided…the author of the article covers this. That's why they mentioned the "patching circus".

And the "Update" part explains what the solution they found was when running Yosemite. Press the "Option" button before selecting the "scaled" button in Display preferences.

The potential answer may be there. So why not try it before responding.

- Nick

I tried the key sequence (option + left mouse click) as mentioned in article and it brought up another resolution choice of 3440 x 1934 .. which when tried did not work either. I set it back to what it was originally (default) 3440x1440.

Getting frustrated .. I pulled all the cables from the Mini and the Monitor (Thunderbolt and power) and let it sit for an hour or so.

Turned it back on - and it worked. Hmm ..

Resolution is at 3440x1440 full screen @ 60 Hz .. which I didn't think it could push 60Hz but the display menu says so .. I won't argue.

Thanks for the help, it was much appreciated.

Bytestream said:

Turned it back on - and it worked. Hmm ..

Resolution is at 3440x1440 full screen @ 60 Hz .. which I didn't think it could push 60Hz but the display menu says so .. I won't argue.

Click to expand...

Congrats! At least you proved that it's possible to do what you wanted to do with Yosemite on your Mini.

- Nick