Stay with 8gb, or put in the additional 6gb I have

So back when I got my M17x R4 I bought it basically barebones aside from the 1080p and 7970 and did the upgrades myself to save money, so one of the upgrades I did was to upgrade to 8gb of ram (2x 4gb), however I have the original 4+2 it shipped with, but I found out recently that it will support dual channel even with miss-matched memory, but I do remember from my desktop building days that 4 sticks is slightly slower than 2 sticks, so it is worthwhile adding that 6gb into the 2 free slots to go to 14gb, or just leave it at 8gb as I'm not sure any game I play even needs or will use more than 8gb.

 

Run AIDA, bench your current memory, install the additional 4+2, bench again, compare.
If performance variation is less than let's say ~10%, use the extra ram. If you get a serious performance hit, better match them properly.

 

This would be the best way to find out. I just wanna add that we normally recommend to match them so that they perform better.