Deployment Guide

System BIOS
38 Setting up BIOS on 15th Generation (15G) Dell EMC PowerEdge Servers | 508
Memory
Mapped I/O
above 4GB
• Enabled
• Disabled
This field helps in enabling support for PCIe devices
that require large amount of MMIO resources. Enable
this option only for 64-bit OSs.
Note: This option is only available on systems with
Intel processors.
Memory
Mapped I/O
Base
• 56TB
• 12TB
• 512GB
MMIO base default is 56TB. User should not change the
default value unless addressing a known issue.
When set to 12TB, the system will map MMIO base to
12TB.
Enable this feature for an OS that requires 44bit PCIe
addressing.
When set to 512GB, the system will map MMIO base to
512GB, and reduce the maximum support for memory
to less than 512GB. Enable this option only for the 4
GPU DGMA issue.
Note: This option is only available on systems with
Intel processors.
Memory
Mapped I/O
Limit
• 8TB
• 1TB
Memory Mapped I/O Limit controls where MMIO is
mapped.
The default, 8TB, is the max address the system
supports and recommended in most cases.
The 1TB option designed for specific OS which cannot
support MMIO over 1TB.
Note: This option is only available on systems with
AMD processors.
PCIe Bus
Customization
• PCIe Bus System
Allocation
• PCIe Bus Custom
Allocation Option 1
• PCIe Bus Custom
Allocation Option 2
• PCIe Bus Custom
Allocation Option 3
Provide options for customizing the allocation of PCIe
bus ranges to PCIe slots.
This can be useful when connecting complex device
sets to a slot.
PCIe Bus System Allocation uses the normal rules of
the system to allocate bus ranges.
PCIe Bus Custom Allocation Option 1 increases the bus
ranges allocated to the wider slots.
PCIe Bus Custom Allocation Option 2 increases the bus
range allocated to one of the wide slots more than with
option 1.
PCIe Bus Custom Allocation Option 3 allocates the
largest bus range practical to one of the wide slots.
Note that use of this option may cause insufficient
resources to be available for remaining slots and
prevent the system from functioning.
Note: This option is only available on systems with
Intel processors.
Slot
Disablement
• Enabled
• Disabled
• Boot Drive Disabled
Allows you to enable or disable PCIe slots on your
system. The Slot Disablement feature controls the
configuration of PCIe cards installed in the specified