Yep, same here, i have some ocz reaper, 1600mhz, 7-7-7-24, had to knock the voltage upto 1.64v.If there is no problem then there is no problem.
If you do start getting random crashes this is the first place I would look mind.
Minimum voltage for DDR3 is 1.5v
Minimum voltage for DDR3 is 1.5v at 1333mhz, 1600mhz is technically an overclock setting, so if you want to run 1600mhz then you need to up it to 1.65v.
I run 1333mhz at 1.5v just because I couldn't tell the difference between 1333 and 1600.