hardware labs

I need advice. I have the next parts: "D5" from Alphacool XSPC Raystorm Pro EK-FC1080 GTX TF6 HWLabs 480GTX HWLabs 420GTS Alphacool XT45 360. They are currently connected in series: Pump ===> XSPC CPU ===> EKWB GPU ===> Alphacool XT45 360 ===> HWLabs 420GTS ===> Res. GPU OCed to the limit but...