You wanna reset the cmos, there is either a cmos reset button on the back of the mobo by the ports or take out and replace the cmos battery on the motherboard itself.
I will for sure try that. But I am thinking why isn't the overclock stable. People have overclocked the i3-540 to 4.2GHz. There should be a fault, probably. I have 3 fans mounted on my cabinet.