Ram 6400 @ 1066Mhz

I tried to OC my rams but I had some surprises. I describe you;
I put the vDIMM to 2.1V
I test 850-870 Mhz no prob!
I see that some people were able to put 1066Mhz, I test, I boot but when I run CoD4 boom black screen (no reboot)
When I put them to 1000Mhz, I do not even boot ...

I also had some blue screens, but a little good sense, but in 1066Mhz I SuperPI tests dectecte and do nothing. That night I left Memtest running (Windows) it was + -% of 1000 I think and had detected 16 eurs while SuperPI operating smoothly so here's my question, How is it that I boot and 1066Mhz know make SuperPI test and I do not even boot 1000Mhz?

Super PI is a bench of perfs and is not pure enough to judge the stability of a o / c.
You tested at least 32M?
It takes time to adjust timings and voltage level.
Between 425 and 500, there are some intermediate values ...

I think 2.2 is sufficient. I tested 425 - 435 is no problem, but from 450 up to 500Mhz it does boot pas and 533 there, yes, that's what I do not understand

Here I will try again 4-4-4-12 in 450 and 5-5-5-15 if it would try 475 if it would still 500 blocks and if I reduce it to 5MHz by 5MH

4-4-4-12 if you want to test frequency max.