MAX NON-overclocked RAM Speed supported by AMD Phenom II 965 processor

I'm building another computer...using Gigabyte's GA-M785GMT - UD2H MB, and AMD 965 AM3 3.4Ghz quad core processor. I believe the highest NON - overclocked RAM speed supported by this processor is DDR 1333.
Gigabyte's spec shows 1800 (OC) then 1666 / 1333 / and 1066. I cannot get a clear answer from Gigabyte support on this subject. Can anyone answer this? Thanks

... I believe the highest NON - overclocked RAM speed supported by this processor is DDR 1333.
Gigabyte's spec shows 1800 (OC) then 1666 / 1333 / and 1066...

Support for DDR3 1800 (OC)/1666/1333/1066 MHz memory modules
http://www.gigabyte.com.tw/FileList/MemorySupport/mb_memory_ga-ma785gmt-ud2h.pdf

Yes...I am fully aware of the Gigabyte support page and QVL list for this motherboard....but...even though this site shows 1666 as a standard supported RAM speed...email support for it says I must Overclock to get that speed. At the same time...Newegg user posts say they are using DDR3 1600 RAM...but...they do not mention Overclocking. Who knows...