Try overclocking your ram first.
If the ram voltage is already 1.65v, do not increase any further.
If voltage is 1.5v, you have leeway. Max intel recommended is 1.575v. However many ppl also use 1.65v without problem, so the choice is yours.
First ensure your cpu is stable. Reset to stock if needed. IF not confirm your cpu OC is fully stable.
Increase your ram voltage as per desired. Better to overclock with a max comfortable voltage than to try to increase voltage later imho.
Do not adjust your baseclock unless u very serious. Manually input the 4 main ram timings (etc 9, 9, 9, 27). LEave the sub timings on auto
Try increasing your ram speed by one setting (2133 to 2400).
See if can boot. If can try, restart and run memtest86. If pass, boot into windows and run prime95 blended. IF your overclock is unstable, you might see either bsods or core crashes.
If stable, either repeat the process to the next ram speed, or decrease ram timings.
Change ram timings by 1, 1, 1, 3 (etc from 9, 9, 9, 27 to 8, 8, 8, 24).
Go play around with your ram speed and timings until you happy.
If unstable, either decrease ram speed or loosen timings. A way to see if u are actually benefitting is to divide the first timing by ram speed (etc 9/2133). The lower the better.
Memtest86 is not the best to detect ram instability. Prime95 blended stresses ram more.