Hmm, it's really odd that there is no option for 1333mhz because I'm sure that setting would work. Maybe your board needs a bios update.
So if 1600mhz is the only option left, perhaps you could try setting it to 9-10-10-25 at 1.6v at 1600mhz.
I tried also 9-10-10-25 at 1.6v at 1600mhz but failed again to start.
what if I changed cpu clock from 266 to 333? How much would affect cpu temp and is it possible that would increase RAM clock as well?
or in other words, what other options I have to OC my system without affect the stability and the temp?
As I said in my 1st post I'm not planning to change the cpu cooler (I have the standard intel box cpu), and besides I live in Greece where the summer with the aircondition closed the temps in the room are between 25-35c (or 77/95f)