Need help for RAM overclocking (questions about voltage)

[Jeepy31]

My system : 

  Asus Prime Z790-P

   Intel Core i5-14600KF

   Ram kit Corsair DDR5 2x16     CMK32GX5M2E6000C36  XMP 6000 Mhz  36-44-44-96, 1.4V

When enabling XMP without other change, my system is not stable.

After many tests, my system is perfectly stable with the following settings :

- 6000 Mhz  36-44-44-96, 1.2V  (corresponds to XMP but with 1.2V instead of 1.4V)

- 6000 Mhz  36-44-44-96, 1.3V (corresponds to XMP but with 1.3V instead of 1.4V)

(not stable with same settings at 1.1V).

1) Do you have some explanations why I cannot increase the voltage to 1.4V ?  Does it mean that my motherboard is defective ?

2) Is it better to put voltage to 1.2V (closer to reference 1.1V) or 1.3V (closer to XMP profile) ? For what reasons ?

It is probably not significant, but in all my tests, I seem to get  a slightly better performances (bitrate + latency) with 1.2V rather than with 1.3V.

3) Does it make sense ? Is it possible or just related to 'random' aspect of benchmarks ?

Edit : this morning, I get opposite results (1.3V better than 1.2V). Cold PC ? Not significant results ?

Thanks in advance

[Jeepy31]

> If more memory kits are validated they are added to the QVL list.
Sure but my question was : do they validate new memory kits with time ?


Regarding my initial question (Given that my system is stable at 1.2V and 1.3V)
"2) Is it better to put voltage to 1.2V (closer to reference 1.1V) or 1.3V (closer to XMP profile) ? For what reasons ?"

Do you have some answer ?