[Beowulf] Re: Estimating cluster power consumption

[steve_heaton at iinet.net.au]

G'day all

I'd like to throw in my little bit of 1st hand experience on the topic.

I've got a cluster of moboz. A new, "smart" 380W power supply runs one dual P3
and all 4x IDE HDDs. The other 3 nodes each have their own, old AT stype, 200W
power supply (A$10 each).

I was lucky enough to get a loan of the Oz equiv of a Kill-A-Watt and made an
interesting discovery... The old 200W units, just powering the mobo pulled 75.5W
/ 0.5A. The newer 380W unit powering a mobo and the hard drives pulled 58W /
0.4A. Yep, the newer power supply, supporting the same load *and* the hard
drives pulled considerably less power!

Seems the age of the power supplies (ie. the associated technology) seems to
make a considerable difference!

In case it's of interest, including the 3GHz P4 head node:
Idle: Power: 460W (552 Max) / Current: 2.57A
Work (Nbody sims): Power: 510-585W (Max 654) / Current 3A (Max 4.18)
Rating: 0.86 kWHr : $0.09 / hr

Call it A$15 a week =)

Cheers
Stevo