All the non-K i5 and i7 can go up 4.0GHz and is essentially just changing the turbo. Normal turbo speed for your CPU on all cores is 3.6, but will be 4.0 if you set a 42 multi. 4.2 will be for 1 core.

Overclocking through BIOS settings is as easy as ABC.

your temps looks good for higher OC.
Try 4.3-4.5GHz and see if your cooler can still take the heat.
As for the stress test it's all up to you. Of course the longer the test the more confident you are in your OC.
But for me, 20 runs of IBT or LinX are more than enough.

If the current vCore is the lowest voltage you have tried then you might need to increase the vCore.

Your GFlops seems to have dropped maybe due to insufficient vCore.
Try pumping a little more vCore to get 100+

No one selling the pro in Malaysia.
You must import it directly from Coolaboratory website for much cheaper price than the ultra sold by niclasteoh.

That would be roughly 125 GFlops. I understand that Intel recommends XTU or Aida64 for stress testing but for me the only way to check the real stability is the old school - Prime95 or LinX or IBT.

You should add more juice to get more GFlops.

I'm using the PRO.

Since this is a stress test so you would just look at the TJmax of 105C.

Did you mean 3470? I can't find any details on the 3470K
3470 vs 3450
You will never see a difference between these two as the 3470 CPU clock is only 0.1 GHz faster = 3% faster

If you can wait, Haswell Refresh will be (hard) launched in April together with the new Z97 chipset with new features.

If you plan to overclock then the 3570K would be a better choice.
"K" stands for unlocked multiplier with overclocking potential.
But then upgrading from Ivy Bridge to a faster Ivy Bridge doesn't really feel a significant difference in performance.

Average is 2666. 2800 and above is rare.

Playing with old & hot stuff... Delidded 3770K @ 5.0GHz
RAM 2800 11-14-14-35-2T

No plan selling it bro, it's still serving as my daily gaming CPU lol