The bearings on them must be worn out then. They are not always easy to change because of the shroud on the card. Might be easier to use Dell warranty if still under warranty. You can also try blowing them out with canned air. Sometimes dirt can cause issues and it never hurts to blow out a video card after a year or so.
Hi,I put the RTX 3070, the Ryzen 7 5800x and the SSD of the Alienware Aurora R10 PC in a new PC.It has an ethermax power supply, asus rog strix x570 f gaming MB and a Artic Liquid freezer 420 in a Be quiet case. After some time, the fans of the GPU stopped spinning. At least HW Monitor told me they were constantly at 0 rpm. But I can hear and see that every time my pc is on, they fans start spinning for like one second and stop immediately. In a Game the GPU has constantly a temperature between 90 - 115 C
Dell OEM RTX 3070 fans stopped spinning