Hey Jungle, welcome back to OCA. I would have to say that two separate loops are a must in your system. Order of components in those loops won't matter at all as the entire loop reaches an average temp quite quickly. I would put the 980x on the dual rad and the 480's on the triple. I still run the "Warbird" for gaming and day to day stuff and it still is running strong after two years with a similar set up to what you have or are striving to get. Here is a pic
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