koths

Q: 2560x1440 resolution suddenly stopped working. 1080p now the max option available

I have 2010 macbook pro (el capitan) and ASUS H257HU monitor which supports 2560x1440 resolution. Up until yesterday I was able to get the full resolution, but suddenly it stopped working and the max resolution I could get was 1080p.

 

I tried resetting smc and NVRAM, but that didn't help.

 

In safe mode, I followed the suggestion by apple and was able to get 2560 resolution. But restarting the machine reverts it back to 1080p. Holding down the option key and clicking the scaled option does not display any resolution above 1080p.

 

I tried searching and followed a few recommendations, but none helped.

 

Restarting the machine and going into displays sometimes does give 2560 option, but clicking on it makes the the screen turn blue and then it comes back still at 1080p, with no options available in the scaled dialog box. The system preference dialog box hangs up for a few seconds.

 

Has anyone came across this same issue and found a solution. I am not sure why it will suddenly stop working, while being able to work in safe mode but not in normal condition. I had tried deleting the profiles as well.

 

With bootcamp (win 7), the display works fine with 2560x1440.

 

The connector I am using is mini-display to DisplayPort.

 

Any suggestions/solutions will be greatly welcomed.

Macbook Pro

Posted on Jan 18, 2016 7:31 PM

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Q: 2560x1440 resolution suddenly stopped working. 1080p now the max option available

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  • Helpful answers

  • by pedro d,

    pedro d pedro d Jan 20, 2016 7:07 AM in response to koths
    Community Specialists
    Jan 20, 2016 7:07 AM in response to koths

    Hello there, moths.

     

     

     

    It seems you're having issues selecting the desired resolution on your external ASUS display. Great job so far with the troubleshooting you've done. The following Knowledge Base article offers some great information to look over and review, as well as links to some additional troubleshooting content:

     

     

     

    Get help with video issues on external displays connected to your Mac

     

     

     

    Before you begin

    You can resolve many display issues by updating the software on your Apple devices, cables, and adapters. If you can see an image on your screen, check for software updates using the Mac App Store:

    1. Connect your external display and any Apple video cables or adapters that you use with it.
    2. From the Apple menu, choose App Store.
    3. Click the Updates button in the App Store window.
    4. Install any OS X or firmware updates that are listed.

    If you're using a display, hub, extender, or adapter not made by Apple, check with the manufacturer for any updates that might be available.

    If you're trying to connect a 4K display or Ultra HD TV with your Mac, make sure your computer meets the requirements for using these external displays.

    If your software and firmware are up to date, or if you can't see the image on your screen, try the steps below for your specific issue.

     

    {...}

     

    Check connections

    Check the connections to your Mac and external displays:

    • If you're using an Apple notebook, try connecting its power adapter.
    • Make sure the external display's power cable is securely connected and that your display is turned on.
    • If you're using a Mac Pro (Late 2013) make sure your displays are connected to the right ports.
    • If you're using a display hub, switchbox, or "KVM," try connecting your display's video cable directly to your Mac instead.
    • Disconnect the video cable where it plugs into your Mac, then plug it back in to reseat the connection.
    • If you're using a video adapter, unplug the video adapter from your Mac, then plug it back in to reseat the connection.
    • If you're using more than one video adapter to connect your display (the adapters are "chained" together), try connecting the display using only one adapter if possible. Some video adapters can't be connected together. For example, a mini DisplayPort to DVI adapter can't be connected to a DVI to HDMI adapter.
    • If your display has more than one video connection, see if using another connection on the display works. If possible, check to see if using a different display or a different adapter works.
    • Try using a different cable that you know is in working order. Check with the display's manufacturer to make sure you're using the cable they recommend.

    Detect your display

    If you're using an external display, sleep and wake your Mac to make it check for connected displays:
    1. Press the power button on your computer to put it to sleep, or choose Apple menu > Sleep.
    2. Wait a few moments, then press a key on your keyboard or click your mouse or trackpad to wake your Mac.
    If you're using more than one display, and you can see the image on one of the displays, you can also use Displays preferences to check for connected displays.

    Adjust video settings

    If there's no image on your display, try adjusting your display's brightness or contrast. If there's still no image, or the image appears torn or scrambled, try selecting a different video resolution in System Preferences.Adjust brightness
    • If you're using an Apple Display, press the increase brightness key F2 key image  on your Apple keyboard. To adjust the brightness of a secondary display, press Control-F2.
    • If you're using a display that's not made by Apple, check the documentation that came with your display to see if it includes built-in controls for adjusting its brightness or contrast.
    Change your display resolution
    1. From the Apple menu, choose System Preferences.
    2. Click the Displays icon.
    3. Click Default for display. If you see more than one resolution listed, choose a resolution and refresh rate. If the display turns off when you change resolutions, press the escape key to undo the change.
      displays preferences window

    If you can't change the resolution of your display because you can't see an image, restart your Mac in safe mode to reset the display resolution to defaults.

    If starting in safe mode doesn't resolve the issue, reset your Mac's NVRAM and SMC to reset the video ports on your Mac to their defaults.

    Check for third-party display software

    If your display works only when your Mac is started in safe mode, and you have display-related software installed, check with the software's developer for updates, or try temporarily uninstalling it.

     

    {...}

     

    Get more help

    If you've tried these steps and your display still isn't working, contact Apple Support to get more help.

     

     

     

    Thanks for being a part of Apple Support Communities.

     

     

     

    Cheers.

  • by koths,Solvedanswer

    koths koths Jan 20, 2016 8:07 AM in response to pedro d
    Level 1 (0 points)
    Jan 20, 2016 8:07 AM in response to pedro d

    Thanks Pedro. But the solution to reset the display through the safe mode had not helped.

     

     

    Tried other suggestions as well. Like deleting all the preference files from the /harddisk/Library folder as suggested here:

    https://discussions.apple.com/thread/2385757?tstart=0

    But nothing helped.

     

    Here's what did help though and something apple should look into:

     

    Connect the mini-display to DisplayPort connector and power cable to the mac. Close the lid.

    For me the monitor was still in 1080p and no higher options available.

    Restart the mac.

    After reboot, go back to system preference -> display and click on scaled.

    Select resolution 1280x960.(something smaller)

    Restart the mac immediately. the display will be in the previous selected resolution.

    After reboot, go back to system preference -> display and click on scaled.

    Now 2560x1440 resolution is available. Select and the display will go to 2560 resolution.

    (IMP) restart the mac immediately and it will boot into 2560x default.

     

    NOTE: if I open the mac lid, the resolution goes back to 1080p. But I keep my lid closed so don't care.  Hope this helps others figure out.