"When you are looking at this from a business perspective, you want this stuff to work as quickly and as efficiently as possible," said Troy Montfort, data center manager at Spectrum Health Hospitals in Grand Rapids, Mich. When it comes to choosing between a slower server that generates less heat and a faster server, users will probably go for the faster system, he said.

An energy rating on a refrigerator is one thing, but for a server, "it's a whole different world, in my opinion," said Montfort. "In [the] health care industry, when I have a doctor wanting ... somebody's record or [a] look at their CT scan ... he doesn't want to sit and wait for that thing to load; he wants it, and he wants it now."

Montford said Spectrum Health Hospitals completed a 6,000-square-foot data center in May to house some 400 x86-based servers, and RISC-based and mainframe systems, as well as to handle future growth needs. In building the system, Montfort said, the focus wasn't, for instance, on buying the most efficient air-handling system. "I wanted the best thing to cover the needs of what I have now, plus the future," he said.

The energy efficiency of a server "is an important consideration, because we have been dealing with power issues," said Dawn Sawyer, operations managers at GuideStone Financial Resources of the Southern Baptist Convention in Dallas. "It is not the main consideration, though. Our main consideration on servers is processor speed. That's going to trump the energy efficiency of a server."

Even so, energy ratings for servers may have some use, said Sawyer, who is also on the board of directors of the Data Center Institute of Afcom, an association of data center managers. "Anything that is standardized that helps people compare things across the board is a positive." But she said the real hope for energy efficiency and speed will rest with technology developments.