Welcome to Tom's Forums!
If you have an Intel based MOBO you can simply use the XMP setting, otherwise you'll need to set the DRAM Frequency -> DDR3-1333MHz ; DRAM Voltage -> 1.65v {closet value}, and preferably set the CAS Timings per RAM's Spec.
As far as 1.50v vs 1.65v, if your RAM is rated at 1.65v @ Rated Speed e.g. 1333 MHz then you should use the correct values to reduce errors, and no running at rated has very little longevity impact verses Default SPD {e.g. 1066 MHz}.
Q - What MOBO?
Q - What RAM, I prefer a link?