if the temperatur of your system is 40c and low fan is seen, something is wrong. Is your fan fully functional? Try another one to make sure. Get these useless cable out of the way to get a good airflow with the fans. The front fans are intake, the back is exaust.
After, check if your PSU fan is spinning. If not, RMA it or try to get a sort of mod if the fan isn't soldered in...but first thing's first.