Diagnosis
The monitor is losing the video signal intermittently. This is a handshake issue between the GPU and monitor, often triggered by power states or a faulty cable connection.
How to Fix It
First, replace the DisplayPort or HDMI cable with the one that came with the monitor. If that's not possible, use a certified VESA DisplayPort 1.4 cable. Ensure it is firmly connected. Disable power-saving features that can interrupt the signal. In the monitor OSD, navigate to General > Energy Saving and set it to Off. Also, in the same menu, set Auto Off to Off. In Windows, go to Power & Sleep Settings and set both screen and sleep to Never while troubleshooting.
If That Didn't Work
The GPU may be entering a low-power state that drops the signal. For NVIDIA GPUs, open the NVIDIA Control Panel. Go to Manage 3D Settings > Global Settings. Find "Power Management Mode" and set it to "Prefer Maximum Performance." For AMD GPUs, in Radeon Software, go to Graphics > Advanced, and disable Vari-Bright and any power efficiency options.
Heads Up
If you are using a GPU riser cable or a motherboard PCIe slot that is not Gen 3/4 compliant, it can cause signal instability. Try plugging the GPU directly into the motherboard's primary PCIe slot. Also, check for GPU driver updates that address DisplayPort stability.