I learned something about my Pass Labs X350. I have a dedicated outlet for my stereo. It has it's own 20 amp breaker and 12ga wiring to the hubble hospital grade outlet. I use the factory power cord with my amp, but I have a MIT power cable on my CD player and a Cardas hardwired power cord on my preamp. I haven't tried different power cords on my amp based on comments from various people about Pass Labs amps being pretty much impervious to cords. Anyway, back to what I learned. I have my front end powered through a power conditioner but I had my amp plugged into the outlet direct w/o conditioning. After listening to some Patricia Barber CDs that I recently bought, I was getting a bit irritated with sibilance. Some of her CDs exhibit some strong sibilance and that got me tuned into it. So I tried plugging my amp into the power conditioner and found not just that the sibilance diminished but also the highs smoothed out noticeably. I am much happier with this arrangement and I really haven't detected any down side to having the amp plugged into the PC. So, power cords may not affect Pass Labs amps much, but Power Conditioning seems to matter.