cpu fan error

[fireb1ade]

my config:
i5 2500k, asus p8z68 v, cm 690II adv with side panel.....
it just happened now....i worked on my pc at morning for some times nd then went 2 clg...den came back @ noon nd strated on... it showed cpu fan error...i saw through side panel nd fan not spinning....last time it happened some 3/4 months ago nd i had to format c drive...but this time b4 i could do nything, it booted into windows as usual..but fan not spinning...i started asus probe nd it showed fan speed 0....i shut it down..waited until mobo light off..then started ups nd machine..again fan not spinning...i shut it down b4 it went to boot again...then opened side panel nd started d cpu again...fan still not spinning..i pushed d fan by my finger nd it started spinning....everything okay...i shut it down nd started again...everything ok now....but whats d problem guys?....i'm apprehensive...is the fan faulty or its just bychance?

 

[coderunknown]

looks for dust or loose fan plug. This can also be cause of bios error. Check if any latest bios is available and update to it.

 

[topgear]

Possible reasons are :

1. CPu fan gone bad.
2. Bios has some sort of automatic fan control option which won't let the fan spin unless the cpu heats upto a certain limit.
3. The cpu fan pin on mobo malfunctioning - try some other 4 pin fan header .