No, the Ethernet adapter on my PC.
Your card is probably faulty / too old.
Switch to a usb wifi adapter and see if the issue persists. I didn't ask, when your PC disconnects, is it just the Ethernet or the wifi also?
For example does your phone disconnect from your internet when your PC does?
I've got a PC which I think needs a new cmos battery because it has intermittent starting issues. It will only boot after unplugging it for 12 hours. I replaced the power supply, reseated the processor, installed new ram and tried a different graphics card but I can't figure it out.
I'm hopeful a new cmos battery will fix it. Otherwise its a faulty board, I'm not sure. It's a good board.