I agree; it doesn’t look like something Jonathan Ive would come up with but it does the trick. My DIY 30 inch cinema display power supply. I could have bought a second hand one but this one has the advantage of being new and very cheap.
I have a 23" Cinema HD display without a power supply, and until I can get one, I have to assume it's dead (I'd like to determine otherwise; in a pinch, can I use the power supply from a 20" Cinema Display?)
For me, it started with this YouTube movie. A power supply for a 23 inch cinema display will have other technical specificationsthan the 30 inch one. The 23 inch power supply is 90 watt, also 24,5 volt And 3,7 ampère. (The 30 inch has 150 watt And 6,5 ampère) I have always understood that you can use a larger power supply on a smaller display but not the other way around