I was able to understand how to use forward voltage to figure out which supply i needed for COBs but I feel rather confused with the QBs. I have a bunch of QB304s (over 4). HLG's website says to use the HLG-240H-C2100 250 watts (59-119v) or HLG-320H-C2800 320 watts (57-114v) to connect 4 of these lights together. Max current per QB304 is 1600 mA. Max FV per diode is 200mA. I think the site is trying to tell me to run these in parallel. QB304 Board Guide My questions: Should i without a doubt use parallel wiring only? - I assume i need to in order to keep each board below the 1600mA max because in parallel the mA are divided up between the boards. I'm looking at HLG's specification chart. Does "voltage max Vf" mean Forward voltage? If using the 320H driver would i be able to get the maximum lumens out of 4 lights? What setup of drivers should i use to get the best quality of lights out of the lights. I can purchase any number of drivers... not that i want to though.