Hey Donnie. I've found that variables for any given COB project change freely as new ideas and constraints are applied to the puzzle; dimensions for a container, number of COBs, multiple drivers vs. one driver, etc.
That being said, you've got to learn how do the numbers for yourself, otherwise your missing out on some of the headache, which later on raises the level of enjoyment and self-empowerment that arises from doing it yourself (for the most part). I'm not only underlining you, but a bunch of others here on RIU.
At first, it's tricky as all hell doing the math but eventually it becomes second nature and before you know it, your doing the math in your head with no overhanging sweat. The reason I'm stirring the pot is that while Supra and others get a kick out of assisting members, they shouldn't have do all of the guesswork. Furthermore, if your dealing with electricity, you should at least be able to know how to calculate math. It's sort of like a precursor to an activity that could bring you lots of happiness or worse, self-imposed fatality.
And I welcome any arguments and/or negative vibes from others. This is a forum site aye?
Here's my treat; I go off this anytime I'm comparing driver and COB numbers:
http://www.meanwell.com/webnet/search/seriessearch.html