If we are talking a system from scratch thats a different story.
But you can't answer this question accurately because it's based on your system and components currently
I went and bought an uber power cord for my gryphon 300 amp/pre. The audioquest dragon HC.
I'm not even sure I heard a difference i would have to A/B it for hours. The thing is gryphon amps are so well built in their reviews it's often said they sound good with even stock power cords. And I'm also plugging it into a uef 12 se with the Galileo pc so... in this scenario the PC was least important.
You can't view them as individual parts it has to be in the scope of the entire system