Core i7 920 @ 4.0 temps, safe or not?

Yes. Running those at 1.65 at 1914 to match my 191base clck. Gets 24Gbps in WinSAT and like 19 to 21Gbps in Maxmem. I have other setting for extreme timing, but those are secret.

surprisingly, giving vcore AUTO and leave everything as it is. HT is enabled and I guess it's a good thing to have it enabled. I stopped @ 3927MHz by setting the ratio and BCLK to 21x187 and it's running so fine, I've been running for days and not a single problem, any increment can cause the system to be unstable. that's it for now I'm satisfied and it's so fast