HI,
 
It could be many reasons:
 
Which games have you tested on? Each game will demand different the card, so only because on a game a card runs silent doesnt means that it will be like that to every game. Also the look of the game cant say how game will demmand the card.
 
1- Check the temps, on the card with EVGA Precision or other monitoring software, maybe your card is get too hot. If this is the reason check the card cooler, if its not dust, or check your case air flow.
2- the card is set to high performance instead of adaptative on the nvidia control panel, this may cause the card to keep the high clocks all the time, and by that running the fan high speeds.
3- try to do a clean driver install, with a certified driver downloaded fron nvidia website.
4- check you energy properties on windows if its not set to power, cause this may lock the clocks of CPU and GPU at higher values.
5- your PCI-E settings on BIOS could be set to power, or some similar energy proofile on the BIOS, try something as normal ou adaptative.
 
Hope it helps.