I did as you wrote above, but still the same problem.
Thank you anyway for all this so far but if you happen to solve my problem I will know very grateful !
Edit:
I test it :
Also try loosen (higher) tFAW value - in above bios screen that is DRAM Four Act Win Time = tFAW set to sat between 31 and 39 and see
Edit²:
I tested 31 to 39, but still nothing.
Edit: (again

)
I restart Memtest86 and it still detects only 2 strips of 3 but I saw it at the end !
- Slot 0 : 2048 MB PC3-10600 - G.Skill Intl F3-12800CL9-2GBNQ
*XMP*
- Slot 1 : 2048 MB PC3-10600 - G.Skill Intl F3-12800CL9-2GBNQ
*XMP*
I have put Manual not XMP in Bios
Résultat de Memtest86+ V4.00 :
3 pass and 0 errors