GA-P35-ES3G Vcore issue

Hi, everyone

I'm terribly in need of help, i hope someone can help me

I have GA-P31-ES3G paired w/ E4500.

I noticed that speedfan & CPU-Z tell me that my Vcore is 1.28V (EIST & C1E disabled) while the fact is it's set to normal in bios (it's supposed to be 1.315V-1.325V right!?)

What frustrates me is that even though i rise the Vcore, speedfan -& CPU-Z keep telling me that the Vcore is 1.28V. i think this is why it failed orthos at 3GHz even when i set the Vcore 1.48V in bios.

Is there someone who uses the same board as i do ?

if so, please tell me what i missed or what setting & bios do u use to get stable OCing.......

Any help will be greatly appreciated ..

Note: I'm using bios F6

Edit: ***!! i typed the wrong MB on the title. It's supposed to be GA-P31-ES3G. please pardon me.