im in need of a little help (more like a lot) im currenty using a netgear FS728TPv2 poe witch sound like a jet taking off so i decided to change the fans to 40mm Noctua NF-A4x20 FLX Fan the old fans are 12v and the new one are to, this is were the problem starts the old fans have a operating voltage of 4,8v to 13.3v when the noctua has a operating voltage of 6v to 13.3v im finding the new fan spins on at startup but stoppes spinng after a few seconded i have checked the voltage and its showing 4.8 volts at the fan i was wondering as the switch heats up will the voltage on the fan increses please advice dont trust running it with no fan spinning or is it ok to do so as will come on when heats up ? have also check the pinout thats right