You need to choose your CPU carefully.
You've put yourself in a pretty tight box with that PSU.
The Atom330 should be a no-brainer. Anything else, you will want to make certain that the CPU's max power draw fits within the range of the Opus PSU.
One thing to be aware of... Intel CPUs draw all their power from the 12v rail and many (if not all) AMD CPUs draw from the 5v rail.