HP 6005 HP Enterprise/Mid-Market Desktop PC Power Supply Architecture - Page 2

Introduction The HP Compaq 6000/6005 Pro Series and HP Compaq 8000/8100 Elite Series desktop PC products introduced a new PC power supply architecture designed to improve power delivery and efficiency in the face of new and challenging Energy Star and other regulatory requirements. This document explains the new HP power supply architecture and compares it to other power supply architectures found in the industry today. The conclusion will summarize HP innovation and the value it can provide to our customers. It will also touch on the direction we believe the industry is moving in this area. 2009/2010 Power Supply Architecture The following sections evaluate the various power supply architectures used by the PC industry in 2009/2010, including HP PC platforms. This will help define what is and is not considered a standard as the foundation for understanding the new HP Enterprise/Mid-market business PC power supply architecture. Intel® ATX12V Standard Most PC industry standards are centered on the Intel® ATX standard (http://www.formfactors.org/developer/specs/atx2_2.pdf) published in the 1990s and maintained by Intel. This standard defines common points of interconnect between power supplies, motherboards, and chassis that allows components from different suppliers to be interchangeable, increases component leverage, and shortens product development cycles. The primary power supply standard, referred to as ATX12V, defined both the electrical interface between the power supply and motherboard and the mechanical dimensions and mounting interface between the power supply and chassis. The ATX12V electrical power supply interface has been the primary industry standard for over a decade, but even this interface standard has gone through an incremental evolution to keep up with technology trends, such as the transition from PATA to SATA drives. The last major update to this standard was published in 2004 when the 20-pin connector was increased to 24-pins to accommodate the increased power requirements of the industry's new PCI Express standard. The interface standard from the current ATX 2.2 specification is shown in Figure 1 from the Technical Reference Guide for the HP Compaq dc7900 Series. The 24-pin Main Power Connector and 4-pin 12V Power Connector are the key interface between the power supply and the motherboard to supply +12V, +5V, +3.3V, +5VSB, and -12V, as well as some control signals to turn the power supply on and off. In addition to this primary interface, the standard also defines optional connectors to supply additional +5V and +3.3V power, if needed, but this connector is rarely used in current products. There is also an optional header for side-band signals to control the fan speeds. This connector is also rarely used. 2