Compaq ProLiant 8000 Compaq ProLiant 8000 Server Technology - Page 15

TC000603TB TECHNOLOGY BRIEF (cont.) ... Power Supplies System Boards Ambient Probe Power Supplies Processors Temperature Monitoring Circuitry OS Fan Control Logic - Hardware shutdown •-HRaredstart when cool •R es - Graceful OS shutdown - System alert - Restart when cool •S-pSepeed up fans •S y System Fans Figure 8: Schematic diagram of fan control logic. Redundant Processor Power Modules Each processor in the ProLiant 8000 server has its own redundant PPM. An additional PPM is included in the server to power the system board. PPMs are also known as voltage regulator modules. The PPMs deliver the precise voltage required by the processors. Compaq PPMs are programmable and support all current and future versions of Xeon processors. Each PPM has redundant circuitry. If a failure occurs in one circuit of the module, the other circuit automatically takes over the task of regulating power to the processor. Redundant Hot-Plug Power Supplies The ProLiant 8000 server uses one of the newest Compaq technologies to reduce downtime: intelligent, redundant, hot-plug power supplies. The server ships standard with two dual-rated 1150-watt/500-watt power supplies and supports three power supplies for an N+1 redundant configuration. The power supplies are connected to a separate power backplane in the server and include new handles for easier insertion and removal. If one of the power supplies fails, its internal fans will continue to operate and help cool the server. The power supply has an embedded microcontroller and an inter-integrated circuit bus that communicates the status back to the system health drivers.2 The health drivers then send status information to the IMD and to Compaq Insight Manager. 2 For additional details about Compaq's intelligent power supplies, see the technology brief Intelligent Power Supply Technology, document number ECG016/0198. 15