When users attempt to change the screen resolution in CentOS 7, they may encounter various issues, such as a black screen or distorted display. This can be frustrating, especially when working with a desktop environment. In this article, we will analyze the problem, explore potential causes, and provide actionable steps to remedy the situation.
The Problem Scenario
Original Problem Statement: "I see screen on centos 7 after i change resolution."
After modifying the display resolution in CentOS 7, you might find yourself facing a screen that is not displaying as expected. This could be due to incompatibilities between the selected resolution and your monitor's capabilities or misconfigurations in the display settings.
Potential Causes of Display Issues
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Incompatible Resolution: The resolution you selected may not be supported by your monitor. Each monitor has a specific range of supported resolutions, and selecting one outside this range can cause display issues.
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Graphics Driver Issues: The graphics driver might not support the resolution change or may not be installed correctly. This is especially true for older hardware or certain graphics card brands.
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Misconfiguration in Display Settings: Sometimes, changes made in the graphical interface do not translate well and may lead to errors.
Fixing the Screen Issue
Here’s a step-by-step guide to resolve the screen display issue after changing the resolution:
1. Accessing Terminal
If your screen is unresponsive or displaying incorrectly, you can switch to a terminal session by pressing Ctrl + Alt + F2 (or F3 through F6 for other sessions). This will take you to a command-line interface.
2. Resetting Display Resolution
Once you have access to the terminal, you can use the xrandr command to check and set the display resolution. Follow these steps:
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To view available display settings, type:
xrandr -
Identify your display name (commonly
eDP-1orHDMI-1) and the available resolutions. -
To set a safe resolution, use:
xrandr --output [display-name] --mode [desired-resolution]For example:
xrandr --output eDP-1 --mode 1920x1080
3. Editing Configuration Files
If the problem persists, you may need to modify configuration files. Open the /etc/X11/xorg.conf file. If this file does not exist, you can create it using the following command:
sudo X -configure
This command generates a new xorg.conf file in your home directory. Move this file to /etc/X11/:
sudo mv ~/xorg.conf.new /etc/X11/xorg.conf
Make any necessary changes to the configuration file related to resolution.
4. Rebooting Your System
After making changes, it is always a good idea to reboot your system. Simply run:
sudo reboot
Upon restart, check if your screen displays correctly.
Additional Considerations
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Graphics Drivers: Ensure you are using the latest graphics drivers suitable for your hardware. If you're using NVIDIA or AMD graphics, consider installing proprietary drivers for better compatibility.
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Safe Mode: If you continually face issues, boot your CentOS 7 into "safe mode" and revert any recent changes that may have caused the display issues.
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Logs and Diagnostics: Check the log files in
/var/log/Xorg.0.logfor any errors or warnings that can provide insight into what may have gone wrong during resolution change.
Conclusion
Changing screen resolution in CentOS 7 should generally be a straightforward process. However, if you face issues post-resolution change, the steps provided above can help troubleshoot and resolve display problems effectively.
By understanding the root causes and applying the right fixes, you can return to a normal working environment without frustration. For further resources and support, you can refer to the CentOS Official Documentation.
Useful Resources
By following these guidelines, you should be able to address screen resolution issues with ease on CentOS 7.
