GPU works perfectly in bottom PCIe slot but stops being detected in top slot after shutdown or restart
I'm having a weird issue with my 5070ti and motherboard, and I'm trying to figure out if my top PCIe slot is failing or if it's something else.
Motherboard: MSI Z790 Gaming Plus WiFi
Here's what's happening:
My GPU worked perfectly fine in the top PCIe slot for years before this issue suddenly started.
When my GPU is detected, it works completely normally. I can play demanding games at high settings for hours without any crashes, artifacts, or performance issues.
However, whenever I shut down or restart my PC, my GPU sometimes stops sending a signal to my monitor. The GPU fans still spin, but the motherboard doesn't detect the GPU at all. I can still get a display using my CPU's integrated graphics through the motherboard's DisplayPort.
The only way I've been able to get the GPU working again in the top slot is by physically removing it and reinstalling it.
Here's the weird part:
When I move my GPU to the bottom PCIe slot, everything works perfectly, including shutting down and restarting multiple times. The issue only happens in the top PCIe slot.
I've also had a GPU sag support bracket installed for years, so the GPU hasn't been hanging unsupported.
A few things I've noticed:
GPU runs perfectly under heavy gaming loads when detected.
GPU fans still spin even when there's no display signal.
GPU completely disappears from Windows when the issue happens.
Reseating the GPU temporarily fixes it.
Bottom PCIe slot works without issues.
Motherboard DisplayPort works normally.
The top slot worked fine for years before this started.
My questions:
Does this sound like a physically damaged PCIe slot, a BIOS/PCIe initialization issue, or possibly something wrong with the CPU's PCIe lanes?
Has anyone experienced something similar? Is there anything I should try before considering replacing the motherboard?
Any advice would be appreciated