This is a loaded question if I have ever seen one. All things equal, I'd like my desktop PC to use less power, but all things are never equal.
I recently bought and setup a Dell XPS 8500 with an i7-3770, to replace my main desktop which was previously a self-built FX-8120 based system. Power usage hasn't significantly changed, and in fact idle or near-idle CPU most of the time so that really hasn't changed much. It may even be slightly higher consumption at idle now.
On the other hand, I bitcoin mine, and the power usage of a mining video card is very significant, much more so than the difference between AMD & Intel CPU. For example, mining on any nvidia card is nearly 10 times less efficient than mining on an equivalent AMD card.
However, even with the "massive" power consumption of bitcoin mining, with 5+ video cards mining non-stop all month, the change in cost for power is a drop in the bucket, maybe $20-$30 extra at most. In comparison, when I turn the AC on for the summer, the power bill goes up by $50 or more per month.
So in the scheme of things, with CPU power consumption differences that may account for, in a worst case scenario, a difference of a couple dollars a month, I really couldn't care less. It would make much more sense to upgrade to a more efficient AC system, or to replace my awesome 50" Plasma TV with some washed out crappy (but more efficient) LCD TV.
Also, when I look at my computer power usage electricity cost, and compare it to the monthly bitcoin income I am seeing, it makes me care even less about the electricity. You gotta spend money to make money, and with these sorts of returns I welcome it
people's water can burn[/URL] now from the methane in it? No care in the world, right?
Some kid using an extra 10W of power from his computer because he doesn't have the most efficient CPU possible isn't exactly causing a meltdown of the environment.