I used Nvidia's control panel to set the fan speed to 100%, and it definitely got a lot noisier... but the temps didn't really go down. After putting in the 120mm case fan, I noticed that while idle temps didn't decrease the load temps didn't reach 90.
I guess I'll just use a fan controller to decrease the speed (and noise) while idle. Any recommendations for a fan controller that fits well in my case (no screws, it uses the sliding panels)? Also, are there extensions for the fan cables in case they do not reach the controller?