This has been discussed in, among others, "
Want to build a "green" WHS", and, by some builders, in "
What's in your server?".
My machine is running at 70 Watts +/- with the GA-MA69GM-S2H board running a BE-2350, 2GB of PC2-6400, a LiteOn SATA DVD burner and 3x WD Caviar GP 1TB drives. The power factor is just over 0.5 so it's pulling just shy of 140 VA using the stock p/s in a ASUS TM-210 case. (That would be a 300 W Delta Electronics p/n GPS-350AB.) I have since replaced the standard 80mm case fan with an Antec SmartCool 92mm fan for noise reasons, but have not revisited power consumption. I suspect the fan has made no signficant difference.
I could have used a different motherboard, different CPU, slower/less memory, and unplugged the optical drive to save maybe as much as 10 Watts. A PFC supply would have been nice for carbon footprint. If that supply was of lower capacity--closer to the requirement--and higher efficiency, that would have been good for power consumption as well. But power consumption/carbon footprint was not the only variable I was solving for.
Likewise, Microsoft could have done more to design WHS to minimize power consumption like spinning down drives and running CPUs at quasi-sleep power levels. I want my server seamlessly available 24x7. I don't need it at full instantaneous capability 24x7. Of course, they've already spent 15 years trying to get power managemetn at the OS level to work. From what I see on my Vista machines, they still aren't there. For one reason or another--probably application software and drivers that don't work and play well with power management--they only sleep correctly and automatically about half the time.
