I got it.
The ASRock board has a UEFI option to enable max turbo clock on all cores.
This option was OFF but it was still doing it. I reflashed the UEFI and now the setting works correctly.
What a nightmare... after all the hardware is ok so .. that's good.
Despite these good news I am still switching to dual 2670s in my main rig.
I might be showing that in another thread.
Thanks everyone for suggestions. You helped me a lot to get to the core of all this.
This thread can be closed now
........ finally.