Austin, Texas-based start-up Calxeda has announced that it is closing down and restructuring. The company had envisaged a future of high density, low-power microservers, all built around ARM processors.

Major server vendors shared this vision. Calxeda boasted a partnership with HP, and HP called its low power platform "Project Moonshot." However, the first Moonshot systems that HP shipped used not ARM processors, but Intel's Atom chips. One problem that limited uptake and desirability of Calxeda's processors was that they were only 32-bit. 64-bit parts were on the roadmap, but not due to arrive until next year.

Calxeda was no small start-up. It raised $55 million in October last year, for a total of about $90 million, and it had about 130 people on staff. It seems that even these ample resources weren't enough to make its ARM server vision a reality. Company president Barry Evans said in a statement that "Carrying the load of industry pioneer has exceeded our ability to continue to operate as we had envisioned."

AllThingsD reports that an attempted fourth funding round had failed to find investors.

The result of Calxeda's restructuring isn't clear. Evans' statement says that the company remains committed to customers with projects built around its EXC-2000 systems-on-chips, and marketing chief Karl Freund says that the product remains available and will be serviced by whatever company emerges from the restructuring. One source speaking to AllThingsD said that a possible outcome is that HP and/or Dell would buy the company's intellectual property to continue their own ARM server efforts.