Thinking of upgrading my RAM

[tsunami65]

Hi, last year I bought your "Quasar 265i" Intel Core i7 4770K @ 4.5GHz Overclocked Haswell Gaming PC Bundle.
It came with 8Gb of RAM but the idea of upgrading to 16Gb has been bouncing around my head for a while.
However, I read somewhere that I might not be able to sustain the overclock on this setup if I simply added anohter 8Gb of the same RAM.
Is this so?
If so, is there a route to 16Gb that would allow me to sustain the same overclock?
Thanks,

Dave

 

[tsunami65]

Oh, I forgot to mention that this bundle came with a different motherboard from the standard one as the Overclockers tech guys weren't able to get a stable overclock with the stock one. The board it came with is the Gigabyte GA-Z87X-OC. Don't know if that makes any difference.
Yeah, I do quite a bit of image editing and that tends to use up pretty much all my RAM