What does 'Not Optimum Mode' mean?

Last Update date : 2017.10.23

When the Not Optimum Mode message pops up on your Samsung monitor it means that the signal from the graphic card exceeds the maximum resolution or frequency your monitor can support.


Below are some recommended guidelines to try:

Note: Check screen Resolution is set to the Optimum Resolution as recommended or higher.


Examples below:



Monitor Size


Optimum Resolution


15 to 16 inches

1024 x 768

17 to 19 inches

1280 x 1024

20 to 23 inches

1600 x 1200



    Check in Monitor Settings that the Monitor refresh rate is set to 60 Hertz, making sure that the screen resolution is set to what is recommended by PC.


    Check that the graphic card driver is updated, (please check the manufacturer of graphic driver)


 Quick Guide to Access Screen Resolution For Windows 7


Note: For other versions of Windows operating system, the interface may slightly differ, however, the steps below may still be the same.


Step 1:  Click on the Start button 1 on your PC then click on Control Panel. On the top right hand side, select view by Category then click on Appearance and Personalization.


Control Panel 


Step 2: Click Adjust screen resolution.


Screen resolution 


Step 3: Click on the drop down next to Resolution and select the option with recommended.


Recommended resolution 



Note: For advance troubleshooting steps, please download the User Manual to see a list of all compatible screen resolutions for your monitor and then select your model type.


If your monitor displays the Not Optimum Mode error message after a brief inactivity or just after sleep mode then consider replacing your HDMI cable to a DVI cable. This issue is due to the computer and the monitor don't communicate with each other with the correct ACPI settings over the HDMI cable. If you still like to use your HDMI cable then you may have to modify settings on your graphics card, please refer your CPU user manual (graphic card in particular) for more details.


If you require further assistance, please contact Samsung Customer Care using one of the options below.

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