The drive to cut power consumption in the enterprise is hitting full swing as energy costs and environmental concerns cause many IT executives to think green. But so far, most attention has focused on the server side of the house, with few ideas emerging for the other big energy draw: the I/O infrastructure.
That may be about to change with a new effort by Intel to cut I/O energy consumption even lower than the most efficient PCI Express systems on the market. The company unveiled research this week describing a technology that can deliver data for as little as 2.7 megawatts per Gbps at a 5 Gbps rate -- that's about 14 percent of the power consumed by the latest PCIe 2.0 devices.
So far, the company has ramped the system up to 15 Gbps, coming in at only 5.0 mWatts per Gbps.
A number of techniques are at play here, which may take some time to ramp up for commercial production. The system has the ability to dynamically scale the frequency and voltage levels on the transmit and receive ends, and data lines are terminated not by a resistor but a passive inductor. The lack of a clock buffer also saves power, but it means that clock information will vary as it passes through the system, although Intel insists this doesn't affect performance.
For those with more immediate power concerns, there are a number of PCIe devices available that can help you scrimp on the wattage. PLX is outfitting the NEC D-Series storage systems with its ExpressLane switch in a variety of multiple lane and port configurations to boost performance. The company offers up a pretty good white paper here on how it designs switches for low power.
Another low-power supplier is IDT, which recently passed the benchmarks for the PCI SIG's PCIe 1.1 designation. The company delivers a range of devices, from a 4 GBps 8-lane/5-port switch to the 48/12 device that delivers 24 GBps. You can find the data sheets, including power ratings, for individual IDT systems here.
Call it a sign of the times that networking equipment can no longer be evaluated on price/performance alone. Until new designs like Intel's hit the market, cost of operation will continue to weigh heavily on upgrade plans.