Cpu fan not spinning ??

[Treebo88]

hey ive built a i5 build with 16gb ram etc, i put my i5 on untill the ib i7 comes out... now its all good and i left it on overnight, got up this morning and temps are sitting around 30 on like internet usage etc and the fans not actually spinning at all.... is this right ? or will it kick in when it gets hotter ??

Gigabyte z77x-d3h board
hyper x 16gb ram
60gb ocz vertex 3 ssd
650w power supply
ati hd 4850 (untill my 7 series comes in the post)

Please help !!

 

[Treebo88]

sorry peeps scratch that managed to mess with the settings for some reason my cpu fan setting was set to 0 ... weird.... now its kicking in around 40 degres !

 

[moogle]

On some motherboards you can have dynamic fan settings according to CPU temperature. So when you're doing relatively nothing the PC is quiet.

That's what must be causing it.