External monitor has blurry font on a MBP retina

Question

There are indeed countless of these questions, some of them succesfully answered. I recently purchased an ACER R241Y.

I started using Sketch and noticed the fonts quality was noticeably worse when on the Acer.

System Information:

El Capitan 10.11.6 (15G1217)
MacBook Pro (Retina, 13-inch, Late 2013)

Here are the screenshots:

I tried the infamous patch: Force RGB mode in Mac OS X to fix the picture quality of an external monitor, the defaults write NSGlobalDomain AppleFontSmoothing -integer X setting.. I am using a DVI -> Thunderbolt(Mini DisplayPort) cable. (I tried HDMI<->HDMI as well).

Answer 1

The MacBook Pro (Retina, 13-inch, Late 2013) has an Intel Iris 5100 GPU and is capable of supporting an HDMI-compatible device, including 4K, while using one Thunderbolt display or it can support two Thunderbolt displays.

In terms of external resolution, this model supports up to 3840 x 2160 pixels at 30Hz or 4096 x 2160 pixels at 24Hz (using HDMI) or up to 3840 x 2160 pixels at 30Hz (using Thunderbolt).

According to the specs of the Acer R241Y, this has a maximum resolution of 1920 x 1080 at 60Hz. And, according to the user manual, this resolution is achieved using VESA mode.

Possible solutions

1. On your MacBook Pro:

   • REFRESH RATE - As a first step, I would check the Refresh Rate set in your MBP. You can find this under the Display tab within System Preferences > Displays. If you change it, you may need to wait a couple of minutes to ensure the change has taken effect properly.
   • RESOLUTION - I would also double-check you're not using the Scaled option for your resolution. Instead, make sure you have the Best for display option selected - also found in System Preferences > Displays.
   • RESET NVRAM - It may be worth resetting your NVRAM. If you're unsure how to do this, refer to my answer here. Make sure you look under the PRAM/NVRAM heading.

NOTE: If, at any point, the display switches off after configuring options in your Displays System Preference, just press the Esc key to undo the last change.

2. On your Acer R241Y display:

If you're still having issues after checking/trying each of the above, try the following:

• Mode type - If your display is already in Auto mode, manually try each of the others (e.g. Standard mode, Graphic mode, etc) one by one. If it's already on a specific mode, then try it in Auto mode instead.
• Focus - You can also manually configure the display's focus. You should be able to do this by going to the Picture Menu.
• Reset your display - There should also be a Reset option on your display's menu. It may be worth trying this if all else fails.

[EDIT]

Since your issue is around how fonts look, there is also a setting in your System Preferences > General. Maybe try ticking/unticking the Use LCD font smoothing when available option to see what difference that makes.

Answer 2

I was experiencing a similar issue on an LG external monitor and just figured it out.

LG has a setting called SuperResolution+ which essentially is a sharpness filter and makes movies and pictures look better but makes text look horrible.
https://www.cnet.com/news/ces-lg-tackles-upscaling-with-super-resolution/

Switching off the sharpness filter makes my text appear perfectly.
I wonder if there is a similar feature on your monitor but in any case this answer might be useful for someone who has this issue with LG.

Answer 3

There is a fix, after all the research I did, here is how you can fix it: There is something called HIDPI which is required in order for mac to display a decent font on other displays.

Install SwitchResX here https://www.madrau.com/ and then take your mac to recovery mode by Restarting and holding command+R. Then open the Terminal in the recovery mode(from the top bar navigation) and type in 'csrutil disable' and later 'csrutil enable' when you want to reenable it. Now after you disabled it, restart your computer and open SwitchResx:

1- If you find the resolution of the monitor in the resolution list with the mark HIDPI then you just click and you are done!

2- If not go into the custom resolution, select from the scaled resolutions

3- create a resolution of your monitor but put double amount for each side pixels. Ex. If your monitor is 1920 by 1080, do 3840 by 2160. Save it and then restart the computer

4- Go back to the list of resolutions and your created resolution should be there.. Look for 1920x1080 with HIDPI mark.

You can go back to recovery mode then to reenable the security. BOOM!

Answer 4

I have been having this issue on/off with an LG UM95...34 something. It's a 34 inch 3440x1440 21:9 ultra wide. Anyway, it was fine for ages and then recently went back to being what I would call... over-sharpened. It's painful to look at close up.

The last thing suggested here (reset monitor settings on the actual monitor) seemed the least effort so I tried that first et voi la! It's back to its normal smooth self. Recommend trying that first.