Prioritization of Power Cords

There are a number of PCs on the market specially designed or optimized for digital components, e.g. Triode Wire Labs, JPS Labs, and plenty others.  I wonder how they different from a PC for another low-powered component...

In general, you want your quietest power on your sources and then on the amplifiers with the most voltage gain.  As gain drops, it becomes less sensitive to power line noise, so power amps are less of a concern by comparison.  This is a general case, the fact is you never want power line noise to enter your system.   I agree with Elizabeth - listen and decide for yourself.  :-)

@twoleftears right, that is what I was wondering - "what is the definition of source?" To me, it could be my DAC/Streamer or it could be the wall to my conditioner. 

It sounds like there could be some benefits elsewhere along the chain as well including the passage between the conditioner and amp. 

I seem to remember this was asked not so long ago, and surprise surprise, there was no unanimity.  However, I think the majority opted for the connection between wall and the power distributor/conditioner.  In a sense that is the "source", even for the other sources.
Right now, I have an Isotek Synchro on order.

John Rutan(audioconnection) believes you should put the best power cord on the source.
For me it is my Ayre DAC. And, I got the AQ Thunder from Johnny, and I have to say it made a positive change.
I also put some on my Ayre monoblocks, and though I have heard Ayre equipment isn't affected by power cord changes, I did notice a significant change in sound. 
Bob