Macbook Pro grinding fan noise

Hi,

After going through this problem here https://discussions.apple.com/thread/5139645 I now think that my Macbook Pro crashes at random because of dust or something inside. The fans sound awfuly strange; this is what they sounded like at worst when I started the Macbook some days ago: http://www.youtube.com/watch?v=NYNnPYfPd_w&feature=youtu.be Then it gets more quiet, but is still pretty noisy all the time, even during sleep mode.

CPU temp: around 40-60°c

Fans: around 2000 rpm

So, I get random crashes (which may be related to the craphics card, but I'm still unsure) and this fan noise. Would replacing the fans + cleaning the inside stop the crashes or should I replace the whole logic board (which my Apple Reseller suggested, but will cost a lot more) ?

Thanks!