Haddy - On a lot of the newer m/bs that feature can
not be turned off in the BIOS.
ECU - be careful what you plug into the m/b fan headers. They aren't usually rated for higher current draws. If you hook up a fan(s) with too high a current requirement you can burn out the header traces on the m/b (depends on m/b and which fan connector it is).
Unless you are running a waterblock on your northbridge, easiest way is to just move the northbridge fan to the CPU fan header
