I agree with Patty, only use batch numbers as a loose guide, as all chips vary even when they come from the same batch.

Both of my 920's have identical batch numbers, and they are totally different in regards to overclocking.

I am really frustrated with my chip, I got it to run 20 passes of LinX using all available RAM, so I started Prime95 Blend, and when I checked it this morning, it has crashed, and reset my system.

I am using 1.3375v Vcore (1.312v in CPUZ idle, and 1.291v under load), Vtt is at 1.355v, IOH 1.140v, QPI PLL 1.200v and the rest are at stock.

I don't know what I need more of to get it stable, whether it be Vtt, or Vcore, or even both.

It is driving me nuts to say the least.

How high would you guys say is the safest amount of Vtt and Vcore for 24/7 use?

It is really annoying, because my chip will do 200x20 with Vcore at 1.264v, and QPI @ 1.335v, and it is both Prime and LinX stable, and I have been playing games for hours on end without a single issue, so I would have thought that my system would have been stable with the Vcore and Vtt voltages I mentioned above, but it just doesn't want to happen..

Turbo mode must demand quite a bit of extra voltage, as this is the only thing I am changing to get my chip up to 4.2GHz..

I will keep tinkering with it though, as I don't give up easily!

It is bound to run at 4.2GHz stable, it's just a matter of finding the sweet spot with my voltages in order to get it stable!!!