Would you happen to have some power consumption figures from the old server to the new server?
Can be done (I will take some photos), but I have to find a reliable True RMS power meter. Should not be difficult at Department of Electrical Engineering. Answering to later posts I must say that measuring power consumed by modern PSU is not that easy and using cheap power meters can give unreliable results, as current waveform is heavily distorted.
It would be very interesting to show simply how you can update your hardware without overspecifying (moving a 500MHz box to a 400MHz box, rather than a ~5GHz box) and save power, money and earplugs :)
Unfortunately the old box is retired already, it has HDD and network board dismounted, so I cannot measure its power consumption.
Even for the Efika we don't have super-hard figures on it (as the board can be configured many ways with graphics or other adapters and different spin-rates of disks or compactflash..)
My server Efika has no gfx board (it is not needed as soon as you install sshd). Konwing that IDE interface of Efika is not ultra fast, I've used low-power 4200 rpm hard disk.