Will the data center of the future call for a greater number of smaller servers, or is it about to make a u-turn back to the days of the big mainframe? Or will it be something else entirely?

The question is prompted by Intel's recent proposal of the "microserver." According to the vision laid out by Sean Maloney at the Intel Developer Forum, the future belongs to smaller, cheaper and more energy-efficient servers powered by the company's Xeon 3400 processors. The plan is for a 45-watt version later this year and then a 30-watt device in early 2010.

As most datacenters have already adopted distributed architectures over centralized mainframes, the goal now is to allow enterprises to rapidly scale up their server capabilities without breaking their power envelopes. A key component in the strategy, naturally, is high-speed networking to ensure data can find its way in and out of the labyrinth of servers, and the multiple VMs within those servers, and then out across the data center proper and onto the cloud.

A glimpse of this future can be seen in the new SGI CloudRack X2, the new 14U cluster representing a combination of former SGI software and Rackable Systems' previous CloudRack device. The machine provides 216 x64 cores, along with a pair of switches and three power supplies.

Of course, SGI would have to contend with Dell, which already has a series of low-cost 1U servers based on the 3400 series. At less than $800, the PowerEdge R210 is only a one-socket model, but it provides an Intel 4320 chipset, a PCIe x16 slot and can accommodate up to 2 TB of SATA storage. It can be configured with 2.5-inch drives or SSDs.

Not everyone is convinced that the future will be smaller, however. Research and Markets just put out a study arguing that as the cloud goes mainstream, small distributed architectures will be less effective. The theory is that, with computing power, performance, capacity and just about everything else that is in limited supply suddenly infinitely scalable in the cloud, reliability will take center stage. And on that score, only mainframes offer the needed memory, cache and reallocation to keep things humming.

The idea of low-cost server technology will certainly be welcomed by small businesses, at least until the comfort level of the cloud increases to the point where critical data can entrusted to it. The question is whether major organizations will find it worthwhile. Low power on an individual machine is well and good, but if you increase server density on the shop floor, you may well end up with even more energy consumption per square foot with only a marginal increase in processing power.

However, the folks at Intel aren't stupid. It would be surprising if they put significant time, energy and money into a project like this without crunching the numbers first.