Observe flickering or black screen issues following GPU replacement.
Observe flickering or black screen issues following GPU replacement.
I recently changed my GPU from a 3090 (Founders Edition) to a 5080 (Founders Edition). I also upgraded the power supply from 850W to 1200W. After that, one of my monitors occasionally goes black. It happens sporadically—about once every half hour, though it shuts off for 2-3 seconds before the image resumes. A notable difference between the two models is the orientation of the output ports on the PCB: they’ve been flipped 180 degrees compared to the previous generation. The monitor uses HDMI, while other monitors use the remaining three DP ports. Right now, I’m trying a few troubleshooting steps—replugging the HDMI and power cables multiple times over the past couple of days, checking connections, etc.—but nothing resolved it. Still, based on my past experiences with monitors flickering, I suspect a cable or connection problem is likely (signaling issue). I’ll experiment further and consider ordering a new cable. I’m mainly sharing this because I have three questions:
a) How could a GPU upgrade cause this regression? Could an HDMI cable gradually fail when handled or bent?
b) Is it realistic for a GPU to have connectivity problems on just one port?
c) Do you know of any cases where a monitor would briefly go black before powering up again? For instance, I’ve had an old Acer FreeSync monitor blink for 3-4 years during gaming. Even after trying various cables (both DP and HDMI), driver reinstalls, or changing output ports, the problem persisted. I got a new LG monitor, gave the Acer to my partner to test—success! Moving the monitor between people fixed the issue entirely. Still, I’m not sure what was the root cause.
It seems checking the GPU settings made a difference. The monitor behavior changed after swapping GPUs, and I spotted some strange display changes. I wasn’t sure about the resolution/refresh rate on the blinking screen—maybe it was off (should be 1440p at 60 Hz). I’ll test it again to see if it improves. Thanks!
These are standard cables that can fail easily from any number of issues. Frequently they get damaged by plugging, unplugging, bending, or twisting. Sometimes you manage to avoid problems and keep the cable in good shape—luck plays a big role. If LMG’s truespec cables work well, they’re likely to move into display versions. High-end ones probably do, but quality and longevity usually follow. I own a 960 with a dead HDMI and a 30080Ti that got water damage, which cracked its DP port twice. One was a cheap, weak cable with a hard bend; the other was a failing backlight from an old Sceptre monitor used as a home display for years.
Running additional tests now. The configuration looks like Desktop → HDMI1 → KVMP switch → HDMI2 → monitor. But with my MacBook Pro using KVMP (MacBook → HDMI3 → KVMP → HDMI2 → monitor), I haven’t seen any problems, so I’m confident the HDMI2 cable, switch, and screen are working. This helps focus the issue on Desktop and HDMI1. Since I’m dualbooting, I’ll switch to that system temporarily to check further. If it still works, it’s likely a Windows problem; otherwise, I’ll reinstall drivers/OS and try again. If the issue persists on Linux, it could be hardware-related between HDMI1 or the GPU. For HDMI1, I’ll test with a different cable. For the GPU, the connection might be too loose—though I’ve already re-plugged it multiple times. My case has metal cross-beams in the PCIe slots near the 5080’s display outputs, which could interfere. During setup, the output ports were partially blocked by those beams, forcing a GPU reinstall at launch. If that doesn’t resolve it, I’m probably dealing with a GPU fault.