Do I need upgraded power cables?

People knowledgeable about electricity will tell you a power cable is a power cable and won't make any difference. People that are members of the church of audiophilia will tell you the differences "aren't subtle" (a favourite). 

 Maybe my components aren't audiophile enough to justify purchasing upgraded power cords. 

You won't know until you try it. Do you buy from dealers, or used? 

If you have a relationship with a good dealer see if you can borrow a good demo ($1000+) high current capable power cord from them, put it on your amp, plug it directly into the wall and see what difference there is. 

If you hear a difference you will have to decide whether that is worth the asking price, and that will answer your question "Do I need upgraded power cables". 

Puritan Labs PS 106 is reasonably priced power conditioner/surge protector, $1300.  Yes, I run one on a smaller system.  Patrick Cullen power cords are price/performance terrific.  Yes, I run those in the same smaller system.

Balance need be struck considering your system.  Nothing outrageous in price.  Enjoy the ride and results.  Cheers

You could borrow AC cables from the Cable Company and try different brands that way.  The rental fee is 10% of the value of the cables, and you can apply that to the cost of any cables you buy from them. They discount some of their cables. I have been very pleased with their customer service, and other Audiogoners have also praised their customer service.

I have been pleased with Cardas AC cables on my preamp and amps.

Based upon the recommendations from @erik_squires (very knowledgeable), I recently purchased a Furman P-2400 AR (the 20A version of his above recommendation) and the Furman PSD 8D, with very good results. 

The 2400 provides voltage regulation, conditioning, surge protection & isolated banks for analog & digital (6 each). I use it for my main components & is full. 

The 8D does everything except voltage regulation, with 4 each isolated banks. I use it for my secondary components (6 of 8 outlets). 
I purchased both for less than $1,000 ($3,800 retail). Highly recommended. 

On upgraded PC’s, never A/B’d, but just bought them… Audioquest NRG Z3 for amp, Y3 for remaining components. Reasonably priced & look good. Don’t know if they improved SQ, but did once buy a Pangea PC that actually degraded sound, so reasonable to assume one would see improvement with the right PC’s.