Intel today launched an Atom system-on-chip (SoC) line that combines extremely low power usage with server-class features, including virtualization technology and Error-Correcting Code (ECC) for higher reliability.

The Intel Atom S1200 chips are for microservers as well as storage and networking systems that need energy efficiency and enterprise features that—Intel says—you just can't get in ARM chips. Intel called the S1200 "the world's first 6-watt server-class processor," and said microservers using the chip will be able to fit 1,000 nodes into a single rack.

ARM may dominate smartphones and tablets, but Intel hopes to lead the way in bringing smartphone CPUs to data centers. (As we've previously reported, Intel is making Atom-based SoCs for PCs, phones, and tablets as well.)

"Right now there are no ARM-based enterprise-class servers," Intel VP Diane Bryant said at a press conference for today's announcement. In addition to the hardware-assisted virtualization and ECC features already mentioned, Bryant noted that the Intel S1200 chips are 64-bit and support the x86 software prevalent in today's data centers.

The prospects of ARM servers from AMD and the likes of Calxeda are intriguing, but ARM isn't a major player in the data center yet. With Atom S1200, Intel hopes to pre-empt ARM's entry into the server market.

To prove the Atom chips' usefulness, Intel trotted out partners HP and Microsoft to talk about servers that will use the S1200 SoC and Windows Server's support for the new product line.

Describing the importance of 64-bit, Microsoft's Windows Server lead architect Jeffrey Snover said, "the benefits of a large, flat address space are just critical for a server operating system, so much so that Microsoft stopped supporting 32-bit chips [in Windows Server] a couple of releases ago. We're very excited that we'll now have a very low-energy part that could run the demands of Server."

Intel also scored support from Facebook. Facebook isn't using servers based on the chips yet, but had one of its top executives on stage with Intel to tout the new architecture's potential.

Facebook's involvement is interesting given that the social network previously joined AMD in touting the launch of ARM-based chips for servers. AMD's server processors using 64-bit ARM chips won't arrive until 2014, however, so Facebook may simply not want to wait.

There are three Intel Atom S1200 processors with frequencies of 1.6GHz to 2.0GHz, and power usage from 6.1 watts to 8.5 watts. Each SoC has two physical cores that can run four threads thanks to Intel's Hyper-Threading, and up to 8GB of DDR3 memory.

Intel's recommended price is $54 per chip in quantities of 1,000 units.

Smartphone CPUs in Facebook data centers

Today, Facebook VP of hardware design and supply chain Frank Frankovsky said, "Xeon-class processors have helped us scale Facebook very effectively so far." But not every workload needs what Frankovsky called "brawny cores."

Now that "smartphone-class CPUs" for servers are 64-bit and include ECC, they're ready for certain parts of the Facebook infrastructure, he said.

"We've applied what I'll call brawny cores unilaterally across our environment," Frankovsky said. "What's interesting about these smartphone-class CPUs is we can right-size them to the needs of maybe the photo storage tier, for example. Maybe that's a great place to start, where we don't need a brawny core, what we need is maybe a smartphone-class CPU that also includes 64-bit and also includes ECC."

(UPDATE: Another Facebook executive told GigaOm that Facebook is not actually using these latest Intel chips in its data centers. Frankovsky's remarks at the Intel event do show that Facebook is interested in the architecture, so perhaps the company will adopt future versions of the Atom SoC.)

Frankovsky noted that you might need two or three times as many Atom (or "wimpy") cores to do the same work Xeon-class processors handle, but ultimately come out ahead when measuring "how much useful work you can get done per watt and per dollar."

Those advantages only exist for certain types of workloads—the key is different CPUs for different applications. According to HP, compute-intensive applications still require Xeons, but the Atoms will be appropriate for "light scale-out applications" such as static Web serving and in-memory caching. HP said its calculations show Atom processors doing twice as much performance per watt as Xeon for light scale-out apps, but only half the performance-per-watt of Xeon for compute-intensive ones:

HP is hedging its bets, going both with Atom and striking a partnership with Calxeda on ARM-based servers. In addition to HP, Intel said systems based on the new Atoms are coming from Accusys, CETC, Dell, Huawei, Inspur, Microsan, Qsan, Quanta, Supermicro, and Wiwynn.

And of course, Intel is working on the next generation of Atom, code-named Avoton. "Available in 2013, Avoton will further extend Intel's SoC capabilities and use the company's leading 3-D Tri-gate 22 nm transistors, delivering world-class power consumption and performance levels," Intel said.

Intel noted that next year's Xeons based on the Haswell architecture will also have impressive energy efficiency, but of course they will still require more power than the Atom SoCs.