Yeah you're right, I didn't realise it already had water cooling capability. You won't need any water blocks for them then, but you will need fittings. One of the first things you will need to do is design your water cooling loop. For example are you going to have all your components connected in series or in parallel? I have mine in parallel which means I need larger diameter tubing and a pump with a high flow rate, but this does mean that I am not pumping hot/warm water from another component onto the next one in the loop. So get a pen and paper and choose how everything will be fitted, where each component will go in the loop eg. Where your CPU water block will be, gpus will be, radiator(s), pump and reservoir. Then decide on the flow rate, which will give you an idea of the pump you will need. Work out how much water is in the system and that will give you an idea of the size of reservoir you need. Also make sure you get fittings for all your components that are compatible with the tubing you have chosen. I can only tell you so much on here, I would watch some videos on YouTube to get a better idea, just type in watercooling tutorials, there are hundreds of videos on the subject