Four sticks RAM boot failure after XMP activation

[florent.t]

Hi,
I just changed my motherboard. I've now the Gigabyte GA-970A-DS3P. With an AMD FX 8320 CPU. And I have 4 sticks of RAM (16 go total) from two kits. Exact same model (Ballistix Tactical 4GB DDR3-1866 UDIMM BLT4G3D1869DT1TX0CEU - 9 9 9 27 - 1.5v). I restored the bios defaults and enabled XMP. The timings are corrects as well as the voltage. So far so good. But when i reboot, it says there is a boot failure (probably because of a hardware incompatibility, blabla).
Do you know why it is not working?
NB: it works with the defaults but at 1333Mhz...
Hope you can help me...
Thank you!

 

[kanewolf]

The FX8320 is well known for only running four sticks of RAM at 1333. I was never able to get mine to run at 1600 even with a fully matched set of four DIMMs.

 

[florent.t]

The FX8320 is well known for only running four sticks of RAM at 1333. I was never able to get mine to run at 1600 even with a fully matched set of four DIMMs.

Hi, thank you for your answer. I didn't know that :/
So you think I should not enable XMP and let the frequency at 1333 Mhz?
I tried with only two sticks in dual channel (in the right sockets) for test purpose and XMP is working. But only the bios says it is now at 1866. Windows 10 in task manager says 667 MHz...
Do you think the difference between 1333 and 1866MHz will be noticeable?