m17x r3 ram upgrade - 12gb (2x4 2x2) possible??

hey guys, I got a pair of 2gb on my r3 (the ones that came by default - made by Hynix, I think and runs at 1333MHz, no idea 'bout the timings, though) now I want to upgrade by adding another pair of 4gb sticks, will these work? and how should I place them? currently, the pair of 2gb are placed on the slots underneath.. so if I am going to add the 2x4gb, should I place them both on the slots underneath the keyboard?? will this "12gb" setup work? also, my brother asks if he can have one of my 2gb, so can I make do of 10gb set up? how should I place them up?? quite a noob on how these ram modules work, or rather asymetrically work.. so thanks guys in advance..

oh btw, i'll be adding a pair of these, if it has any bearing, http://www.gskill.com/en/product/f3-10666cl9s-4gbsq because of its availability in my area and quite cheaper than the other ones available, I didn't opt to get the 1600 because I read that it would only run at the lowest speed (being a 1333 attached ), I don't wanna ditch the extra 2gb because I feel like it's a waste to not use it.. I need your advice guys. thanks again!

 

It should work.. However it strongly depends on how fussy your motherboard is when mixing the RAM.... Most likely it will work but buy it from somewhere which has a return policy just in case...