faalin :
no the h100i is a all in one closed loop and can not be added to. A custom loop you would have to buy each component.... water block's, rad, pump, res, fittings, tubing, coolant. you can start off with just a cpu loop and later add more to it to cool video cards or even the motherboard.
Very true, the H100i is closed loop but he only wants to cool his CPU, not GPU, RAM etc.
I have answered his question... He wants to cool his CPU, thats it.
There is no reason for a custom loop just for his CPU.