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You'll need to download the program Core Temp to check the VID (default voltage) of your chip, it'll vary a bit from one 2500k to another.
No because when Intel make the chips they don't all turn out exactly the same, the VID (or default voltage) is around 1.2V from what I remember, but like I said it'll vary a bit from one chip to another.
My VID (coretemp 0.99.8) fluctuates constantly........ dunno quite what to make of that!