Dave Donatelli is really into Project Moonshot. The head of HP division that makes hardware for data centers said in his HP Discover keynote Wednesday that the company's line of microservers was “game-changing.”

Moonshot, he said, was “the most important server invention … made in a decade.” It is so important because, by HP's estimates, about 10m servers will be added in data centers around the world in the next three years, and it would take too much power and data center space to make them traditional rack servers.

While “we'll sell x86 servers for years and years and years,” Donatelli said, there is also huge need for something different. “You have to reinvent what a server is and what a server can do.”

Moonshot is HP's answer to that need: a tiny low-power server node optimized for whatever application it is running.

“We will build all kinds of different cartridges for all kinds of different applications,” Donatelli said. “That's what we call software-defined server.”

The vendor has Moonshot cards for x86 chips, it has them for ARM, and it has a single card that supports both. Moonshot cartridges have been designed to support x86 and GPUs (Graphics Processing Units), Texas Instruments chips and DSP (chips inside television sets).

A 64-bit ARM cartridge is in the works.

“It's all about matching the server to your application to get you the best combination of power, performance and cost. This was an innovation we've been working on for more than 10 years at HP Labs, and again, we think this is a revolution.”

Some of the customers already using Moonshot servers include PayPall, LeaseWeb, Savvis, Purdue University and HP itself. Meg Whitman, HP president and CEO, announced in her keynote Tuesday that all of HP.com had been moved to Moonshot servers.

“We are now powering the entire site on the equivalent of 12 60-watt light bulbs,” she said.

The idea of matching hardware to the application is something big internet companies like Google, Facebook and Microsoft have been doing themselves. These companies have designed their own servers and went directly to manufacturers in Asia to get them built, since the traditional vendors (HP included) had been competing in designing middle-ground servers that were trying to be everything to everyone.

In addition to specs driven by the application, Moonshot is about high density. A single enclosure currently holds 45 cartridges, and ten such enclosures can be installed in a single rack.

These would use 90% less power than HP's DL380 servers delivering the same computing performance would use. This capacity would also be in one rack instead of nine and cost 77% less.