The Raritan Blog

The density war continues….

Posted on September 28, 2012 by Herman Chan

I read today that HP released its Proliant DL560 Gen8 Server Series with support for 4 Intel Xeon CPUs, each CPU supporting 8, 6, or 4 cores. In addition, up to 1.5 TB of memory and 5 hot plug drives are supported.  And, to boot, you get ALL this in a compact 2U package.  That’s a lot of horsepower to help support increasing virtualized workloads.

Now, how would you power such a beast.  Well, it comes with a pair of 1200W highly efficient 80 Plus rated power supplies.  If you decide that you want to pack 20 of them in a 42U rack, you’d need to provision about 16KW of power to each rack in a rack iPDU with at least 20 C13 outlets.  How did we get to 16KW?  We made a simple assumption that the server may run @ 65% of nameplate or ~780 watts.   780 watts x 20 servers is just about 16KW.  Your mileage will vary depending on what you decide to use as an nameplate de-rating assumption.  Typical ranges fall somewhere between 60-70%.  Given this, your choices to power a rack full of these will likely be one of 2 options depending on whether you’ve got 208V 3 phase or 400V 3 phase coming into the cabinets.  They are: (A) a pair of 208V, 3 phase, 60A rack iPDUs providing 17.3KW of power or (B) a pair of 400V, 3 phase, 30A rack iPDUs providing 16.6KW of power.  Check out our iPDU product selector to find the one that suits you.