You have to hold the fan while do the test, the idea is know if the noise comes from the fan or not.
I get what you are saying, and ill give it a shot, but just thinking about it, the problem is that the cooler is vibrating. Considering that the fan is the only moving part of the whole thing, I'm sure that its causing the vibrating. The problem is that the while cooler vibrates so much that it makes a very rapid ticking noise. Now I guess im wondering if the fan is not balanced right or something that is causing the excessive vibrations, though there is no way to know unless I get a new one