Tracking the issue Observing the situation Addressing the concern
Tracking the issue Observing the situation Addressing the concern
the affected screen is a BenQ EX3501R 35 Inch Ultrawide 21:9 UWQHD (3440 x 1440). The issue began when I turned off the monitor using its side button while the computer stayed on with sleep music playing. For a month, turning it on and off by the button caused the flash screen to flicker quickly, followed by rapid switching of the Windows display. Eventually, I had to toggle the monitor multiple times before it worked properly. The Windows settings were set to 60MHz, but I stopped using the sleep mode and started using a blank screensaver instead. Recently, I adjusted the monitor's frequency to 100MHz in Windows and went for a walk with my dog. After an hour, the monitor entered a loop showing the Windows screen before going blank again. I turned it off, and now only the brief BenQ flash appears, followed by the Windows display briefly. The light indicator stays on when active. Parts tested so far suggest the problem isn’t related to the graphics card. I’ve checked all four GPU outputs, but the HDMI 2.0 cable worked fine on another monitor, indicating it’s not the issue there. I’m able to test both monitors with the PC connected, and Device Manager shows drivers are installed without errors. The BenQ frequency can now be lowered to 30MHz, 100MHz, or 60MHz, but the problem persists. I don’t have any other ideas to try, or any advice on whether it’s worth fixing.
30mhz could damage your vision, 60mhz does so more gradually. New monitors should operate at 75-144mhz. If you suspect a power button issue before testing, remove cables first. DisplayPort isn’t suitable for high performance, but HDMI 3.0 is better. Is the monitor still covered by warranty?