There are many many guides in the Rampage section that you should spend some time reading, they cover basics and more in depth detail if you want it.
Bottom line is cooling in your instance. If your cooler can manage it you will get good frequency.
Here is what I would do.
Mode of OC XMP profile - that sorts your memory out.
Multi set to 42x
Vcore to offset mode
+
0.02
Set your SATA mode if you are running a RAID
Leave all else on AUTO
F10 and save
Now you should have a stable 4.2GHz OC and your ram is running at spec.
If you want more then read and get into your bios and have fun with it.
Post up any issues or questions you might have.
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