i7 7700k with a gtx 1080. it has one fan, different from those that have 3 fans. unsure why its only one fan
my cpu has a liquid cooling with 2 fans
thats my computer
If you are experiencing high temps then an extra fan won't hurt and they are pretty cheap. I am guessing you have a blower style card which draws air from inside the case. The more cool air it gets the cooler and quieter it will run.
i added in 2 intakes and it didint affect anything at all so im returning them
gpu gets around 80 degrees so the fan in gpu gets loud af