Question is 1.37 volts safe for gskill ripjaws ram?

BIOS adjustments and OC will not void warranty, however if some physical damage occurs then that would void warranty.

Extra frames is always good, some times may not seem that much especially when comparing high speeds, however where DRAM is most helpful is increasing the minimum. Comparing max FPS 150 and 170 will seem like minimal difference, however minimum FPS 60 vs. 80 would be significant.