ElCaron:
It is probably not a good idea to go for the max rating. At least not if you do not want to dimm all the time.Also, are you under the impression that voltage source with a max rating of 3A works like a constant current source above that load? Because that is in general not the case. It will overload and break.
That's what I was afraid of. So if I was gonna do something like that, use a bigger psu with a BIG current limiting resistor. I updated my previous post with a wild idea that I had.