Intel squeezes power for server processors down to 50 Watts
Intel has added two low power server processors to its product range in the form of the 45-nanometer Xeon L5420 and L5410 processors, which run on the FSB1333 front side bus at a maximum clock speed of 2.5GHz or 2.33GHz and include two 6MB L2 caches. Whilst a Xeon E5420 requires an 80 Watt thermal design power (TDP), the low voltage quad cores have just a 50 Watt TDP. The older 65nm four core processors achieved a maximum speed of 2.0GHz (Xeon L5335) at this power consumption. The quad core Xeon L5408, which is aimed at the embedded market, at a speed of 2.13GHz and FSB1066, has a 40 Watt TDP.
Intel's 1000-unit OEM price for the Xeon L5420 is $380, and $320 for the L5410 . This is $64 more than the 80 Watt Xeon E5420 and E5410 models respectively.
The power consumption of the main processor plays a significant role in the overall energy requirement and efficiency of a server, but varies significantly depending on the processor load and clock speed, and other system components such as the chipset, power supply, hard drives and memory modules also have a significant effect. In many Xeon servers, the fully buffered DIMMs consume more power than the processors at a low processor load, which reduces the efficiency of the server. Economic Xeon servers with two memory channels for registered DIMMs are now possible using the 5100 chipset codename San Clemente. However their performance is poor compared to machines with four channel FB DIMM memory controllers.