Hello,i am going to buy 4gb single stick for my new build and my motherboard has to dimm slots,so if i buy a single stick 4gb and upgrade it to one more single stick 4gb with exactly the same brand ( corsair vengence in this case) will they work in dual channel?If not,will they at least work as 8gb,will i notice a difference between dual-single channel RAM in gaming? Thanks in advance.