I'd have to agree with Litlratt on that one. If you have components that put a draw on the PSU that's close to 80% of the total output of said PSU, you start going beyond it's efficiency & you might see more of a draw by the unit.
I think the best way to lower the power consumption would be to do what you did by going nearly naked on the folding PCs. Out of curiosity gibby, did you ever hook up a Kill-A-Watt device to one to see what they draw? I'd like to know how close it is to that site where you can estimate the size of PSU you will need.