I know some graphics cards will kick out warm air rather than cool air, but airflow is more important than absolute temperature, especially if the NB is very hot.
This applies also to the tower style CPU coolers which have become so popular. Unfortunately, these can raise NB temperatures since the (warm) air from the CPU cooler blows directly at the case rear exhaust, resulting in less airflow along the motherboard's surface. This can raise VRM temps too.
A side intake fan may help.
Something else I often do is put a vented PCI slot cover in one or two of the PCI slots, to get more air moving across the lower half of the motherboard; I typically have negative case pressure (more exhaust than intake), so cool air gets drawn in through the vented slots.
The years just pass like trains. I wave, but they don't slow down.
-- Steven Wilson