watercooling loop question

[venomous41]

im planning on moving to a new case and had plans of running 2 loops. 1 loop for cpu and full m/b block. 2nd loop for a single gpu right now, maybe 2, but that will be much further down the road.
here is the stuff i have for both loops, then ill ask the question.
right now im running a heatkiller 3.0 and a ek full block on a evga classy. black ice 2x120 rad. or that would be a 240? 1/2id/3/4od hose. mcp350 pump connected to a xspc mirco res.
the 2nd loop that i dont have connected yet, will be a XSPC X20 720 Pump/Res a swiftech 240 rad, 1/2id hose on a ek gtx580 block.
ok, now for the question. should go with what i have and do 2 loops, or go with 1 loop using a combo of the parts i have? maybe use a 360 radi with the mcp350 and micro res? or get a different top for the 350 and use a bigger res?
im putting this all in a danger den waterbox plus. i know a single 360 rad will fit, but 2 240 will require a little modding i think, and there is no place to mount that x20-720 pump/res.
any thoughts?

 

[crapito]

remember the KISS rule: Keep It Simple Stupid

use just 1 loop, assuming your radiator is large enough. seems like a lot of clutter and more work with dubious rewards for separating your liquid cooling.

 

[venomous41]

thats why i decided to rethink the whole thing.

 

[Goty]

Your temps for your downstream components will be warmer with a single loop than they would be with dual loops. You've got plenty of rad to do it either way, but you really need to keep restriction into account. That BI rad is fairly restrictive and with three or four blocks in the loop, your flow rates are going to tank.