GPU not being detected by computer

[anchored]

I've had my current setup for years and suddenly my GPU has stopped being detected, instead my computer shifted to using the integrated graphics of my Intel CPU. My GPU's fans still spin once my computers turned on, so it's still connected. I've tried downloading the latest drivers, but they can't be installed because the installer can't detect any AMD hardware. About a week or so ago when I turned my pc on, the tower would start up normally but the monitor would remain black as if it weren't connected to the computer at all, but after changing where the HDMI cable was connected to in my tower my monitor began working normally.

Is this the cause of the issue? Would my GPU only work if my HDMI is connected in a specific area? If so, I don't see why it wouldn't be detected at all even if my HDMI cable is connected to a different output.

GPU: R9 280 series from AMD

 

[Ralston18]

Update your post to include system hardware specs and OS.