There are few possibilities as to what '(OC)' means, so what MOBO and CPU?
Your CPU-z is for a Lenovo Notebook, OEM BIOS e.g. HP, Dell (most), GW, Lenovo, etc will NOT allow you the mofify the DRAM Frequency beyond the CPU and/or Chipset Rated/Allowable Defaults.
Oh that is my laptop, I have all of the parts of my desktop in except the RAM which I am planning on getting from the store, in person. The ASUS motherboard supports up to 1866 (OC) I think it might go higher but I would not plan on experimenting that high anyways.
I dont remember the specific motherboard but I know it is an AMD FX-4170 CPU