Zotac GTX 980: fans keep spinning up every few seconds even after power is *disconnected* when HDMI cable is plugged in.

I have a Zotac GTX980.

(I noticed that my GPU fans started to rattle lately.)

This morning, I noticed a regular noise from the fans *while the machine was powered off. I checked, and the GPU fans span up every few seconds, immediately stopping again. It seems that both of them are not synced.

I unplugged the power and switched off the AC, but the fans kept spinning. I unplugged HDMI and now the fans stopped spinning.

• what causes this?
• how can I stop this?
• how likely is it that the constant spinning was undetected and caused the fans to rattle (I fear that they will fail soon :( )
• is fixing a larger standard fan onto the gpu a valid way to replace the failing fans? (after removing the original fans)

The machine is running Win 7 (so Windows GPU drivers). The screen is a LG MU67. It's powered on; my other (running) machine is plugged into the screen on the other HDMI port.

Submitted February 27, 2018 at 04:25PM by poiu- http://ift.tt/2GNUfzr