is it me or is itt really that increasing batch number makes CPUs less exiting, the first batches of D0 used to overclock better than current batches and uses less voltage!

I have a D0 3923A and I need 1.36v @ CPU, 1.22@ QPI/DRAM and 1.81@ PLL just to reach 4.2GHz, if I want to reach 4.4 which is the maximum I could achieve with my R2E then I have to ridiculously increasing voltage as following:
1.46@ CPU, 1.32 @ QPI/DRAM and 1.89@ PLL !!
That's with Blck 210, any thing higher than that and it is very instable at any voltage also any thing higher than 213Blck and the PC won't POST.
I have to add that IOH and ICH needs a bump in voltage also.