help with voltage please

[soundesciple]

Can anyone tell me the max safe voltage of a phenom 2 x 4 955 be Deneb c3
ive looked on the AMD site but can`t see a max voltage, only a max temp.

 

[soundesciple]

cheers, ive got it at 3.9 with 1.5 volts and looks stable running Prime small FFT`s at the moment but wasn`t sure if i could go any higher with the voltage. temps have topped out at 55c so looking good for my first oc attempt