I'm bored waiting for my parts to show up so I thought I would get some more of my questions out of the way. My build will be done using citi 1818 chips which according to this data https://cobkits.com/product/citizen-clu048-1818-90cri-choice-of-color-temps/ can run up to 250w. I plan on running them at 50-60w. How do you determine the efficiency rating at the wattage you are running at? A cob rated for 250w and only running at 50w is only 20% efficient? That can't be right. Keep in mind this question is coming from an electronic dummy. Pipes