Hi everyone,
I’m experiencing an issue with my PC monitor and would appreciate some advice.
Device: HP Pavilion Gaming Desktop
Operating System: Windows 11 Pro
Monitor: Acer Nitro 24-inch Full HD Monitor
Recently, several red vertical lines started appearing on my screen. The lines are visible all the time, including on the desktop, in applications, and sometimes during startup. They seem to stay in the same position and do not disappear after restarting the computer.
Things I’ve tried:
- Restarting the PC
- Updating the graphics drivers
- Disconnecting and reconnecting the monitor cable
- Using a different HDMI cable
- Changing the screen resolution and refresh rate
The red lines are still present, and I’m not sure whether the issue is caused by the monitor, graphics card, display cable, or a software problem. The PC otherwise appears to be functioning normally.
Has anyone dealt with a similar problem? What usually causes red lines to appear on a PC screen, and are there any troubleshooting steps or repairs I should try before replacing any hardware?
Thanks in advance for your help!
If the red vertical lines are showing all the time (including BIOS/startup) and stay in the exact same position, that usually points away from software and toward a hardware issue.
Since you already tried a different HDMI cable and driver updates, you’ve basically ruled out the easy fixes.
At this stage, the most likely causes are:
Failing monitor panel (Acer Nitro display issue)
Faulty GPU (graphics card artifacting)
Less commonly, a damaged display port on the GPU or monitor
A quick way to narrow it down:
Try connecting your HP Pavilion Gaming Desktop to another monitor or even a TV
If the red lines disappear → your Acer monitor is the problem
If the red lines stay → the issue is likely your GPU
Also, if possible, test the Acer monitor with another device (laptop/console). That helps confirm whether it’s the screen itself.
If the lines are truly visible from startup and never change position, in most real-world cases it ends up being a failing display panel or GPU memory issue, and unfortunately those aren’t fixable with software.