Forceware 175.16 and fans

[my_lo]

Hello guys, i have a little question concerning the forceware 175.16 and the behaviour of my nvidia 7900 gs fans.

I have a dell XPS 710 with a nvidia 7900 GS, it is provided with the 90.41 drivers. Normally the fans of my gfx card start to spin when i launch a game and stop 1 or 2 minutes after i quit the game. It's been turning like that for a year and it was always fine. Then came Age of conan and a lot of graphic problems due to my non updated drivers. I then updated the drivers to the forceware 175.16.

Since then, the fans of my 7900 GS start to spin when i launch a game but then they stop after a minute. I can go on to play for 2-3 hours and the fan doesn't spin again. If i do an alt-tab to browse the web and then come back to my game, the fan restart to spin but stop after a minute. I haven't seen any artifacting yet nor crash or freeze but i'm worry that it could happen and destroy my graphic card. I checked the temp with ntune and it goes between 65-75°c and it says that the speed of the gpu fan is 180 rpm.

So my question is as follow: is it normal or should i clean the drivers and go back to my old ones (i don't play aoc anyway) ? Is it an updated way of controlling the fan speed in function of the temp? So far, i see an improvement of the graphics and the framerate (compared to the 90.41 drivers) but i don't want to destroy my card...