I Don't know the answer, but watch the Vtt Intel spec is 0.3 to 1.4 v

For 21x200 you'll need more vcore.. 1,4v is no problem with a good air cooling. 

For 30x133 I need only 1,05V VTT.. 

but when u start to oc over BLCK - then it goes tricky.
Whats up with 32x133?

Please post your complete settings, pwm frequencies, PLL & PCH etc. 

If you want to OC here is some good Info

http://www.overclockers.com/3-step-guide-overclock-core-i3-i5-i7/

post your settings, and we will see.
There is no "ideal bios setup" ... for 4,2 GHz .. it always depends on the cpu quality.

I need for absolut stable 4 GHz 133x30 1,325 Vcore in Bios. This is in windows 1,34 - under load 1,32V.
Tested with prime (12h), linpack (50runs), some games and 12 Youtube vids at the same time. 
But my watercooling system did not allow the cpu to get higher than 50°C on cores :D
And.. it's very important to know, that good cooled cpus need more Vcore than an air-cooled one. Why? Can't explain in english - but it "electric resistance" has someting to do with it . ;)

If you use E-Leet to find the max settings, set everything in BIOS on standard. No overclocking.. everything must be stock.
And then go to E-leet and tune .. test... tune ... etc. 
then you'll  find the max oc-settings.
After finishing that, go to the bios and set the parameters which are stable in E-Leet there.

For 4480 MHz I need more Vcore, also more VTT then 1,05V.. but I can't build it at the moment stable.. my PSU is to small (620W).
Waiting for the new seasonics ;)

sorry for my bad english.. 

VCore 1.35V (BIOS) + 0.13125V in E-Leet = 1.48V  

have you C1E and C-Tech States C6 disabled?

Try it on the other way.
Find out a good BLCK.. like 150 or 160.. something like that. Try it with multi 22.
Look to it that youd don't have to push to much vcore,... search an efficient BLCK. 

Do it only with bios - left e-leet for this time of testing.
Then, put the multi higher, step by step, vcore pushing, vtt pushing when instable.
Look every time on the temps. 85°C should be the max on cores (10% secure room)

And set 
CPU PWM to 847 or higher
other PWM to the highest 4xx
PCIE only to 100 under 200 BLCK. There is no need for "double-post". Disable GenGlock.

Try it.

Ok - that means 1.35V Vcore or 1.48V Core?
If only 1,35V needed, try 1,4 with 28x160.. :D

The oc with BLCK got more benefit in the benchmarks, yes.

Here is 1 more point.  The Vtt should always be within 0.5 v of the DIMM (memory) voltage.  So, for your (and mine) 1.65 v on memory, we should have at least a 1.15 v on Vtt (mine is 1.2 v).  Also per Intel Vtt should be between 0.3 to 1.4 v. 

What version is the standard Bios?
You've to use A70.. but I was wondering if you have an other version.. 
because, only the A70 enables the "K" Functions.. or?