My graphics card gets hot when playing KB!

[Metroplex]

This isn't a problem per se, as I can still play the game comfortably and at all settings maxed, I have a 3.0Ghz dual core processor, 120G of space, 2G of RAM and a 8600GT 500MB Nvidia card, yet this is the only game (and Crysis on med) that makes my graphics card whine and spin like there is no tomorrow! It gets hot aswell after a short time of playing KB, all my other games play fine and the card is as quiet as a when underload, my drive is defragged daily using Auslogics disk defrag but it still makes a lost of noise, do you experience this problem too? Write!