Hi and welcome to the Gigabyte Forum.
Well the good news is that as long as the memory is the same as the first set it should work fine, with a bit of tweaking.
The bad news is that you have now got twice as much as me!!!
You are going to have to amke sure that you have marked the two sets diferently so that you can tell them apart.
Next the memory voltage is going to have to be increased to make up for the extra loading on the memory controller. If the default is 1.65 increase this to1.68 -1.72v start low.
You will need to increase the QPI/Vtt also to somewhere between 1.22 and 1.45v. This will have to be played around with until you get stability.
Make sure that your Uncore is set to twice your memory multiplier or twice plus one or two. So if your memory multiplier is 10 the Uncore should be 20-22.
OK I will leave you to play now. Let us know how you get on.