and do you know how these buffalo will overclock? or any other elixir.
should I buy them?

I also see that in the link you post elixir is a bit rectangular, while these buffalo look like a perfect square.
maybe hynix that are more square and have 3 rows of info? also the first row is similar:
512821 in hynix and 512845 in buffalo.


is there any link about how do more or less every IC overclocks?

dont know,
if they had written D9GKX it would be easier to identify them and i would be happier.....LOL