38 IBM eX5 Implementation GuideFigure 2-18 UEFI System Settings panelFor more information about system-specific UEFI options, see the following sections: IBM System x3850 X5: 6.9, “UEFI settings” on page 259 IBM System x3690 X5: 7.8, “UEFI settings” on page 337 IBM BladeCenter HX5: 8.5, “UEFI settings” on page 3962.7.1 System power operating modesIBM eX5 servers are designed to provide optimal performance with reasonable powerconsumption, which depends on the operating frequency and voltage of the processors andmemory subsystem. The operating frequency and voltage of the processors and memorysubsystem affect the system fan speed that adjusts to the current cooling requirement of theserver.In most operating conditions, the default settings are ideal to provide the best performancepossible without wasting energy during off-peak usage. However, for certain workloads, itmight be appropriate to change these settings to meet specific power to performancerequirements.The UEFI provides several predefined setups for commonly desired operation conditions.This section describes the conditions for which these setups can be configured.These predefined values are referred to as operating modes and are similar across the entireline of eX5 servers. Access the menu in UEFI by selecting System Settings OperatingModes Choose Operating Mode. You see the four operating modes from which tochoose, as shown in Figure 2-19 on page 39. When a mode is chosen, the affected settingschange to the shown predetermined values.We describe these modes in the following sections.
