Dell PowerEdge R650 EMC BIOS and UEFI Reference Guide - Page 15

Table 16. Integrated Devices details (continued) Option Description disabled right before the operating system boots. This option is set to Enabled by default. NOTE: When there are multiple add-in graphic cards installed in the system, the first card discovered during PCI enumeration is selected as the primary video. You might have to rearrange the cards in the slots in order to control which card is the primary video. I/O Snoop HoldOff Response Current State of Embedded Video Controller SR-IOV Global Enable OS Watchdog Timer Empty Slot Unhide Memory Mapped I/O above 4 GB Memory Mapped I/O Base Slot Disablement Slot Bifurcation Selects the number of cycles PCI I/O can withhold snoop requests, from the CPU, to allow time to complete its own write to LLC. This setting can help improve performance on workloads where throughput and latency are critical. Displays the current state of the embedded video controller. The Current State of Embedded Video Controller option is a read-only field. If the Embedded Video Controller is the only display capability in the system (that is, no add-in graphics card is installed), then the Embedded Video Controller is automatically used as the primary display even if the Embedded Video Controller setting is set to Disabled. Enables or disables the BIOS configuration of Single Root I/O Virtualization (SR-IOV) devices. This option is set to Disabled by default. If your system stops responding, this watchdog timer aids in the recovery of your operating system. When this option is set to Enabled, the operating system initializes the timer. When this option is set to Disabled (the default), the timer does not have any effect on the system. Enables or disables the root ports of all the empty slots that are accessible to the BIOS and operating system. This option is set to Disabled by default. Enables or disables the support for the PCIe devices that need large amounts of memory. Enable this option only for 64-bit operating systems. This option is set to Enabled by default. When set to 12 TB , the system maps the MMIO base to 12 TB. Enable this option for an operating system that requires 44-bit PCIe addressing. When set to 512 GB , the system maps the MMIO base to 512 GB, and reduces the maximum support for memory to less than 512 GB. Enable this option only for the 4 GPU DGMA issue. This option is set to 56 TB by default. Enables or disables the available PCIe slots on your system. The slot disablement feature controls the configuration of the PCIe cards installed in the specified slot. Slots must be disabled only when the installed peripheral card prevents booting into the operating system or causes delays in system startup. If the slot is disabled, both the Option ROM and UEFI drivers are disabled. Only slots that are present on the system will be available for control. Slot n: Enables or disables or only the boot driver is disabled for the PCIe slot n. This option is set to Enabled by default. Auto Discovery Bifurcation Settings allows Platform Default Bifurcation, and Manual bifurcation Control. This option is set to Platform Default Bifurcation by default. The slot bifurcation field is accessible when set to Manual bifurcation Control and is grayed out when set to Platform Default Bifurcation. NOTE: The slot bifurcation supports on PCIe slot only, does not support slot type from Paddle card to Riser and Slimline connector to Riser. Serial Communication To view the Serial Communication screen, power on the system, press F2, and click System Setup Main Menu > System BIOS > Serial Communication. Pre-operating system management applications 15