Which is why I mentioned GPUs, which use similar levels (on the high end)
the same thing.. no gpu runs at the wattage that a hashfast or cointerra asic is going to run at these things are using hundreds of watts 24/7, and not peaky like a graphics card. and yet again, no graphics card has as many asics on it, nor as much power requirement as a high end bitcoin miner. the sheer amount of power that these things will draw compared to a graphics card - significantly more power required. this isn't just take a graphics card power circuit and multiply by four. its not that easy.
Actually, the most difficult part of building a reliable VRM is dealing with transitions...so according to what you just stated, ASICs would be easier since they fluctuate less....however, I disagree, I think ASICs power will fluctuate a lot as we know that hashing is a very volatile activity.
Plenty of GPUs run at around 250W TDP...thats about the same as the ASICs in the CoinTerra box...I've owned and overclocked many of them. I have a little idea of what I'm talking about
I've traveled the world overclocking competitively...these pictures are from a North American championship I won in 2009...
http://s161.photobucket.com/user/miahallen/slideshow/GOOC2009I've actually won two NA championships and a world championship