How could one determine?

[MAbans]

I have 4 xserves, how can I determine how much power is actually being used, is there some sort of utility out there or equation someone can go on? Any help would be great..

 

[Giaguara]

Which generation of Xserves?
I don't think they can be reliably measured with software only, as software can't take everything into account. It can see if all cores are being used on the new processors, but that itself will not be all that is needed for making up the math.

The Xeon processors in the new Xserve consume a maximum of 80W per processor,
providing more computation capability in the same thermal profile as the previous-
generation Xserve—for a tremendous boost in performance-per-watt. In addition,
the Xeon 5400 series processor has enhanced power management features that, in
conjunction with the power management of Mac OS X Server, reduce the idle power
to as low as 4W. Spread across the typical daily workload of an Xserve, lower idle
power can greatly reduce average server power consumption, lowering both power
and cooling bills.

- that's all I could find from the newest models http://images.apple.com/server/docs/Xserve_TO_20080108.pdf

 

[limike28]

P3 International makes Kill A Watt products. You could plug your XServes into them and track it.
http://www.p3international.com/products/consumer/p4320.html