Oh, lets play the power game. A1X1K takes how much power on the average in a 24 hour period? G5 for the same. take the difference times what the average power company is charging @ watt hour and find where the total cost point is. I expect it to be close to if not exceeding a decade.
Exactly. It's like when I really wanted to get a TDI here in the states. People were so desperate for them that dealers could and were marking them up 5-10000 dollars ABOVE sticker. Because they could. so, a 24k car turned into a 29-30k car. It would have taken decades to see the money saved in fuel efficiency and repairs. So I went with a 15k rabbit gasser. not nearly as fuel efficient, but really fun to drive.

I have heard this argument elsewhere. If you are going to get this anal, you need to factor in the electricity and energy cost it took to print the new board, assemble it, etc, as well as the resource drain. The sunk cost for the older hardware was paid for long ago. The only time that electricity argument is going to hold water is if you are operating server farms.