Dell PowerEdge M820 Systems Quick start guide

ii PowerEdge M820 Technical Guide
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June 2012 | Rev 1.0

iii PowerEdge M820 Technical Guide
Table of contents
1 System overview..................................................................................................................................................................5
Introduction.........................................................................................................................................................................5
New technologies ............................................................................................................................................................. 6
2 System features ...................................................................................................................................................................7
Comparison of PowerEdge systems ...............................................................................................................................7
Specifications ..................................................................................................................................................................... 8
3 Module views and features............................................................................................................................................. 10
Module views.................................................................................................................................................................... 10
Module features ................................................................................................................................................................13
4 Processors ..........................................................................................................................................................................15
Processor features............................................................................................................................................................15
Supported processors......................................................................................................................................................16
Chipset................................................................................................................................................................................16
5 Memory...............................................................................................................................................................................17
Supported memory ..........................................................................................................................................................17
Memory configurations ...................................................................................................................................................18
Memory speed ..................................................................................................................................................................19
Memory RAS features...................................................................................................................................................... 20
6 Storage ................................................................................................................................................................................21
Internal storage .................................................................................................................................................................21
Storage controllers.......................................................................................................................................................... 22
7 Networking and mezzanine cards ................................................................................................................................ 24
Select Network Adapters................................................................................................................................................ 24
Mezzanine cards .............................................................................................................................................................. 26
8 Power, thermal, and acoustics ...................................................................................................................................... 27
Power consumption and energy efficiency................................................................................................................ 27
Power supply units .......................................................................................................................................................... 28
Thermal and acoustics.................................................................................................................................................... 28
9 Operating systems and virtualization ........................................................................................................................... 30
Supported operating systems........................................................................................................................................ 30
Supported virtualization ..................................................................................................................................................31
10 Dell OpenManage systems management.................................................................................................................... 32
Systems management solutions................................................................................................................................... 32
OpenManage systems management ........................................................................................................................... 33
Dell server management operations............................................................................................................................ 38
Appendix A. Additional specifications..........................................................................................................................40
Module dimensions and weight....................................................................................................................................40
Environmental specifications ........................................................................................................................................40
Video specifications ........................................................................................................................................................40
USB peripherals................................................................................................................................................................ 42
Appendix B. Standards compliance ............................................................................................................................. 43
Appendix C. Additional resources................................................................................................................................. 44
Appendix D. System board block diagram.................................................................................................................. 46

iv PowerEdge M820 Technical Guide
Table 1. New technologies ................................................................................................................................................ 6
Table 2. Comparing the PowerEdge M910 and M820 ..................................................................................................7
Table 3. Technical specifications...................................................................................................................................... 8
Table 4. Module features...................................................................................................................................................13
Table 5. Supported processors ........................................................................................................................................16
Table 6. Memory technologies supported.....................................................................................................................17
Table 7. DIMMs supported................................................................................................................................................18
Table 8. Memory speed capabilities ................................................................................................................................19
Table 9. Memory RAS features ........................................................................................................................................20
Table 10. Hard-drive backplane options ..........................................................................................................................21
Table 11. Supported hard drives ........................................................................................................................................21
Table 12. RAID controller feature support ...................................................................................................................... 22
Table 13. Supported Select Network Adapter options and features .......................................................................... 25
Table 14. Supported mezzanine cards............................................................................................................................. 26
Table 15. Power tools and technologies ......................................................................................................................... 27
Table 16. M820 acoustical performance......................................................................................................................... 29
Table 17. Primary operating system support .................................................................................................................. 30
Table 18. Virtual guest operating system support ......................................................................................................... 30
Table 19. Virtualization support .........................................................................................................................................31
Table 20. iDRAC7 with Lifecycle Controller functions and benefits........................................................................... 33
Table 21. Feature comparison for iDRAC7 Enterprise and iDRAC7 Express for Blades .......................................... 34
Table 22. One-to-one and one-to-many operations .................................................................................................. 39
Table 23. Environmental specifications ............................................................................................................................41
Table 24. Supported video modes....................................................................................................................................40
Table 25. Industry standard documents .......................................................................................................................... 43
Table 26. Additional resources .......................................................................................................................................... 44
Figure 1. M820 front view ................................................................................................................................................. 10
Figure 2. M1000e chassis enclosure with M820 blades ............................................................................................... 11
Figure 3. M820 internal module view...............................................................................................................................12
Figure 4. QRL code located on module ..........................................................................................................................13
Figure 5. Blade network daughter card (NDC) .............................................................................................................. 24
Figure 6. Dell systems management solutions.............................................................................................................. 32
Figure 7. Systems management server lifecycle ........................................................................................................... 38
Figure 8. Module dimensions............................................................................................................................................40
Figure 9. System board block diagram............................................................................................................................ 46

5 PowerEdge M820 Technical Guide
The Dell™PowerEdge™M820’s scalability makes it a perfect fit for core business applications or
consolidated workloads. Virtual environments supporting large numbers of sizeable virtual machines
will find the M820 a perfect choice. With up to four Intel®Xeon®E5-4600 processors and up to
1.5 TB of RAM per node—12 TB of memory in just a single M1000e chassis—the M820’s remarkable
computational capability and memory scalability can address even the toughest demands. With
Dell’s Select Network Adapter, you can fully customize the I/O capabilities of the M820 to match the
networking technology that’s right for your applications.
Ensure maximum uptime with the fully redundant M-series power, cooling and networking
infrastructure designed to provide the stability and resiliency our customers demand for Enterprise-
class deployments. The M820’s design matches Dell’s commitment to reliability, with features such
as multiple hardware RAID choices and our unique failsafe virtualization technology, which utilizes
redundant SD media to provide failover capabilities for embedded hypervisors.
Help manage your servers using the Dell OpenManage™ portfolio, including Dell’s exclusive
Integrated Dell Remote Access Controller (iDRAC) with Lifecycle Controller. iDRAC, an embedded
systems management feature, allows Dell servers to be managed in physical, virtual, local and
remote environments, either in-band or out-of-band and with or without a systems management
software agent. OpenManage also integrates and connects to leading third-party systems
management solutions you may already use, allowing you to maintain a single point of control and
capitalize on your existing investment. OpenManage simplifies the lifecycle of deploying, updating,
monitoring, and maintaining your Dell PowerEdge servers.
Implement the right combination of features and performance scalability with the PowerEdge M-
series blade servers that can handle tough workloads in any size data centers. In addition to the
world-class management features provided in all PowerEdge servers, the M820 also takes advantage
of the capabilities of the M1000e Chassis Management Controller (CMC). The CMC allows M-series
blades to be managed individually or as groups, in single or multiple chassis, and within a data
center or in multiple geographically dispersed locations around the globe without requiring a single
agent or additional hardware. PowerEdge M-series blade servers use the redundant power, cooling,
and networking infrastructure provided by the Dell M1000e blade enclosure, which is exceptionally
easy to deploy and manage and maximizes power and cooling efficiency.

6 PowerEdge M820 Technical Guide
A number of new technologies are featured on the PowerEdge M820 system, as detailed in Table 1.
New technologies
Detailed descriptions
Intel Xeon processor
E5-2600 product family
This new family of Intel processors has embedded PCI Express®(PCIe) lanes for
improved I/O performance and additional new features. See the Processors
section for details.
Intel C600 series chipset
The Intel Platform Controller Hub (PCH) chip is implemented on the M820.
LRDIMM
This new memory option, load reduced DIMM (LRDIMM), is designed with a buffer
chip (or chips) to replace the register to help minimize loading. LRDIMMs can
increase overall server system memory capacity and speed. See the Memory
section for more information.
Flexible LOM
Dell’s Select Network Adapter options allow you choose the right network fabric
without using up a valuable mezzanine card slot. See the Networking and
mezzanine cards section for details.
Next-generation PERC
options
The M820 supports new Dell PERC controller cards with improved functionality
and faster performance. See the Storage section for details.
Express Flash drives
Dell Express Flash PCIe solid-state drives (SSDs) provide fast performance without
requiring processor resources or capturing DRAM. The M820 supports up to two
Express Flash PCIe SSDs. See the Storage section for details.
iDRAC7 with Lifecycle
Controller
The new embedded system management solution for Dell servers features
hardware and firmware inventory and alerting, in-depth memory alerting, faster
performance, a dedicated gigabit port and many more features. See the Systems
management section for details.
Advanced power
management
The M820 supports advanced power monitoring and power capping tools that can
help manage power consumption in the data center.
Failsafe hypervisors
The internal dual SD module enables Dell's unique Failsafe Virtualization
architecture, ensuring uptime by providing failover capability for embedded
hypervisors, such as VMware®ESXi™.
Fresh Air cooling
Dell has tested and validated an integrated data center solution that enables you to
operate at higher temperatures or even chiller-less. See the Power, thermal, and
acoustics section for details.

7 PowerEdge M820 Technical Guide
Compared to the previous generation of Dell PowerEdge blade servers, the M820 has more
memory, processor cores, and networking options than ever before. Features include DDR3
memory, PCI Express 3.0, a network daughter card (NDC), dual internal SD module, and Dell’s
next-generation iDRAC solution known as iDRAC7 Enterprise with Lifecycle Controller.
The PowerEdge M820 is a replacement for the M910 system. Table 2 compares the features of both
systems. For the latest information on supported features, visit Dell.com.
Feature
PowerEdge M910
PowerEdge M820
Chassis; enclosure
Full-height blade;
PowerEdge M1000e Blade Enclosure
Full-height blade;
PowerEdge M1000e Blade Enclosure
Processors
Intel Xeon processors 6500 and 7500
series, Intel Xeon processors
E7-2800 and E7-4800 product
families
Intel Xeon processor E5-4600
product family
Internal interconnect
Intel QuickPath Interconnect
Intel QuickPath Interconnect
Memory
32 x DDR3 RDIMM and UDIMM
48 x DDR3 RDIMM and LRDIMM
Hard drive bays
(hot plug)
2 x 2.5”
4 x 2.5”
Embedded NIC
4 x 1GbE LOM
2 Dual Port Select Network Adapters:
3 options of 4 x 10GbE
RAID controller
PERC H200, H700, S100
PERC H310, H710, H710P
Express Flash drives
Not supported
Up to 2
I/O slots
4 PCIe 2.0 x8 mezz. card slots
4 x PCIe 3.0 x8 mezz. card slots
Optional SD port
Yes
Yes (redundant hypervisor with vFlash
media)

8 PowerEdge M820 Technical Guide
Feature
PowerEdge M910
PowerEdge M820
Dell OpenManage
Systems Management
Dell OpenManage
Dell Management Console
Lifecycle Controller 1.x
iDRAC6 (Express or Enterprise) with
Lifecycle Controller 1.x, Chassis
Management Controller (CMC) 3.x
OpenManage Essentials
Dell Management Console
IT Assistant
OMSA Agent
OpenManage Power Center (requires
iDRAC7 Enterprise with Lifecycle
Controller)
OpenManage Integrations and
Connections
iDRAC7 Express for Blades with
Lifecycle Controller (standard option)
Table 3 lists the technical specifications for the PowerEdge M820 blade server. For the latest
information on supported features, visit Dell.com.
Feature
Technical specification
Form factor;
enclosure
Full-height blade;
Dell PowerEdge M1000e Blade Enclosure
Processors
Intel Xeon processor E5-4600 product family
Internal interconnect
Intel QuickPath Interconnect (QPI): 6.4 GT/s; 7.2 GT/s; 8.0 GT/s
Cache
2.5MB per core; core options: 4, 6, 8
Memory1
Up to 1.5TB (48 DIMM slots): 4GB/8GB/16GB/32GB DDR3 up to 1600MT/s
Chipset
Intel C600
Video
Integrated Matrox®G200
Primary storage
Hot-plug hard drive options:
Up to four 2.5” SAS, SSD, or up to two Express Flash PCIe SSD
External storage:
For information about Dell external storage options, visit Dell.com/Storage
USB ports
2 front
I/O mezzanine card
options
1Gb/10Gb adapters:
Broadcom 5719 Serdes 4P 1Gb
Intel I350 Serdes 4P 1Gb
Broadcom 57810S-k 2P 10Gb
Intel X520-x/k 2P 10Gb
Qlogic® QME8262-k 2P 10Gb
Brocade® BR1741M-k 2P 10Gb
Fibre Channel:
QLogic QME2572 2P 8Gb
Emulex®LPe1205-M 2P 8Gb
Infiniband:
Mellanox®QDR CX-3 40Gb
Mellanox FDR CX-3 56Gb

9 PowerEdge M820 Technical Guide
Feature
Technical specification
I/O slots
Fully populated mezzanine card slots and switch modules yields 3 redundant I/O
fabrics per blade
Dell Select Network
Adapter (network
daughter card)
2 x 10GbE Broadcom 57810S-k 2P
2 x 10GbE Intel X520-k 2P
2 x 10GbE QLogic QMD8262-k 2P
RAID controller
Internal controllers:
PERC H310
PERC H710
PERC H710P
Power supplies and
fans
Supplied by M1000e blade enclosure
Dell OpenManage
Systems Management
(Agent-free or with
OpenManage Server
Administrator [OMSA]
Agent)
OpenManage Essentials
Dell Management Console
IT Assistant
OMSA Agent
OpenManage Power Center (requires iDRAC7 Enterprise with Lifecycle
Controller)
Chassis Management Controller 4.x (available with the M1000e Modular Blade
Enclosure)
OpenManage Integrations and Connections:
-OpenManage Integration Suite for Microsoft®System Center
-Dell Management Plug-in for VMware®vCenter™
-Connections for HP®Operations Manager, IBM®Tivoli®Netcool®and CA
Network and Systems Management
iDRAC7 Express for Blades with Lifecycle Controller (standard option)
-Upgrade to iDRAC7 Enterprise with Lifecycle Controller
-Upgrade to 8GB vFlash media or 16GB vFlash media for iDRAC7 Enterprise
with Lifecycle Controller
-Trial evaluation available for IDRAC7 Enterprise with Lifecycle
Controller
Operating systems
Microsoft®Windows Server®2008 R2 SP1, x64 (includes Hyper-V®v2)
SUSE®Linux®Enterprise Server
Red Hat®Enterprise Linux®
Virtualization options:
Citrix®XenServer™
VMware®vSphere™
Red Hat Enterprise Virtualization®
For more information on the specific versions and additions, visit
Dell.com/OSsupport.
Embedded hypervisor
Two internal SD cards dedicated for hypervisor
One dedicated for vFlash media support
For more information about the Dell blade solution, see the PowerEdge M1000e Technical Guide or the
M1000e Blade Chassis Specification Sheet on Dell.com.
1GB means 1 billion bytes and TB equals 1 trillion bytes; actual capacity varies with preloaded material and operating
environment and will be less

10 PowerEdge M820 Technical Guide
The Dell PowerEdge M820 implements a new module design that supports up to 48 DIMMS and
four processors. The M820 is a full-height blade server that requires a PowerEdge M1000e chassis
to operate. It occupies one slot vertically in the M1000e for a maximum of 8 blade servers in one
M1000e chassis. The M820 can be mixed with other existing Dell blades of quarter-height, half-
height and full-height form factors.
The following sections provide external and internal views of the system and describe the module
features. For more detailed information on features and descriptions for the M820, see the Dell
PowerEdge M820 Systems Owner's Manual on Support.Dell.com/Manuals.
As shown in Figure 1, the M820 module supports up to four front-accessible, hot-plug hard drives
and three USB ports.
The chassis design of the M820 is optimized for easy access to components and for airflow for
effective and efficient cooling. Figure 2 shows the M1000e chassis enclosure populated with M820
modules.

11 PowerEdge M820 Technical Guide
The M820 module shown in Figure 3 supports up to 48 DIMMS, four processors, and many other
features that are described in this guide.

12 PowerEdge M820 Technical Guide
For additional system views, see the Dell M820 Systems Owner’s Manual on
Support.Dell.com/Manuals.

13 PowerEdge M820 Technical Guide
Table 4 lists the modules features for the M820 system. For additional information on these features,
see the Dell PowerEdge M820 Systems Owner’s Manual on Support.Dell.com/Manuals.
Feature
Description
Three front-accessible USB connectors
Indicator for M820 power status
Four front-accessible, hot-plug, 2.5-inch drives; see the Storage
section for details
Hard drive activity LEDs
Indicate the status and activity
Release button on the front handle of the blade server
Internal USB connector for a USB flash memory key that can be used
as a boot device, security key, or mass storage device
Trusted Platform Module (TPM)
TPM is used to generate/store keys, protect/authenticate passwords,
and create/store digital certificates; it also supports the Intel®Xeon®
TXT functionality
Quick Resource Locator (QRL)
This code on the chassis can be scanned by a smartphone
application to access additional information and resources for the
server, including videos, reference materials, service tag information,
and Dell contact information
The M1000e chassis enclosure LCD control panel is located on the front of the M1000e chassis to
provide user access to buttons, display, and I/O interfaces. For more information on the M1000e
LCD control panel, see the Dell PowerEdge Modular Systems Hardware Owner's Manual on
Support.Dell.com/Manuals.
A useful feature included with Dell PowerEdge 12th generation servers is the Quick Resource Locator
(QRL)—a model-specific Quick Response (QR) code that is located on the server (see Figure 4). Use
your smartphone to access the Dell QRL application to learn more about the server.

14 PowerEdge M820 Technical Guide
This QRL code allows you to:
View step-by-step videos, including overviews of system internals and externals, as well as
detailed, concise, task-oriented videos and installation wizards
Locate reference materials, including searchable owner’s manual content, LCD diagnostics, and
an electrical overview
Look up your service tag so you can quickly gain access to your specific hardware configuration
info and warranty information
Contact Dell directly (by link) to get in touch with technical support and sales teams and provide
feedback to Dell
These codes provide an easy way to retrieve the critical support information you need when you
need it, making you more efficient and effective in managing your hardware.
For more information on the M1000e chassis enclosure features, see the Dell PowerEdge Modular
Systems Hardware Owner's Manual on Support.Dell.com/Manuals.

15 PowerEdge M820 Technical Guide
The Dell PowerEdge M820 features the Intel Xeon processor E5-4600 product family, offering an
ideal combination of performance, power efficiency, and cost. These processors provide high
performance no matter what your constraint is—floor space, power, or budget—and on workloads
that range from the most complicated scientific exploration to crucial web-serving and
infrastructure applications. In addition to providing raw performance gains, improved I/O is also
made possible with Intel Integrated I/O, which can reduce latency by adding more lanes and
doubling bandwidth. This helps to reduce network and storage bottlenecks, unleashing the
processor’s performance capabilities.
The new Intel Xeon processor E5-4600 product family not only adds new features, but also
improves upon many features of the predecessor Intel Xeon processor series. A summary of what’s
new and improved includes the following:
Up to two additional cores and up to 8MB more last level cache
More memory—16 more DIMMs than previous-generation of full-height blade servers with
support for up to 32GB DIMMs, increasing memory capacity up to 1.5TB
Intel Integrated I/O has support for up to 80 lanes of PCIe 3.0, which can reduce latency
Faster connections are provided throughout the system with support for DDR3 1600MT/s
memory and 8.0GT/s QPI
Intel DDIO allows I/O traffic to skip the main system memory and be directed straight to the
processor cache, which can provide a significant reduction in latency as well as allowing
memory to remain in a low-power state
Intel Advanced Vector Extensions offer up to double the floating point operations per clock
cycle by doubling the length of registers, which can be useful for addressing very complex
problems or dealing with large-number calculations that are integral to many technical, financial,
and scientific computing problems
Intel Turbo Boost Technology 2.0 delivers up to double the boost than the previous-generation
turbo technology
Continued improvements to both Intel TXT and AES-NI help to better protect systems and data
For more information on the Intel Xeon processor E5-4600 product family, visit Intel.com.

16 PowerEdge M820 Technical Guide
The M820 supports up to two processors with up to eight cores per processor. Table 5 lists the Intel
Xeon processors supported by the PowerEdge M820. For the latest information on supported
processors, visit Dell.com.
For information on processor installation and configuration, see the Dell PowerEdge M820 Systems
Owner’s Manual on Support.Dell.com/Manuals.
The Intel C600 chipset is implemented on the PowerEdge M820. For more information, visit
Intel.com.
Model
Speed
TDP
Cache
Cores/
threads
QPI
Turbo
E5-4650
2.7GHz
130W
20MB
8/16
8.0GT/s
Yes
E5-4650L
2.6GHz
115W
20MB
8/16
8.0GT/s
Yes
E5-4640
2.4GHz
95W
20MB
8/16
8.0GT/s
Yes
E5-4620
2.2GHz
95W
16MB
8/16
7.2GT/s
Yes
E5-4617
2.9GHz
130W
15MB
6/6
7.2GT/s
Yes
E5-4610
2.4GHz
95W
15MB
6/12
7.2GT/s
Yes
E5-4607
2.2GHz
95W
12MB
6/12
6.4GT/s
NA
E5-4603
2.0GHz
95W
10MB
4/8
6.4GT/s
NA

17 PowerEdge M820 Technical Guide
More memory options are available than ever before with the Dell PowerEdge M820—greater
capacities, higher frequencies, and more flexibility. The M820 supports up to 1.5TB of memory
and speeds up to 1600MT/s, providing high performance in a variety of applications. High memory
density means there is no compromise when it comes to virtualization.
Increase your uptime and reduce data loss, due to Dell’s focus on reliability, availability, and
serviceability (RAS) features. RAS aids in the rapid and accurate diagnosis of faults that require
service, increasing your memory reliability. System uptime is reinforced with RAS features like
memory mirroring, sparing, and many others.
In addition to supporting existing RDIMM technologies, the M820 supports load reduced DIMMs
(LRDIMMs), which use a buffer to reduce memory loading and allow for greater density, allowing for
the maximum platform memory capacity.
Table 6 lists the memory technologies supported by the M820.
Feature
RDIMM
LRDIMM
Yes
Yes
No
Yes
800, 1066, 1333, or
1600MT/s
1066 or 1333MT/s
1, 2, or 4
4
2, 4, 8, 16, or 32GB
32GB
3
3
x4 or x8
x4
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes

18 PowerEdge M820 Technical Guide
Table 7 lists the DIMMs that are supported on the M820. For the latest information on supported
memory, visit Dell.com.
Only
Capacity
(GB)
Speed
(MT/s)
Type
Ranks
per
DIMM
Data
width
SDDC support
Voltage
2
1600
RDIMM
1
x8
Advanced ECC
1.5
2
1333
RDIMM
1
x8
Advanced ECC
1.35
2
1333
RDIMM
1
x8
Advanced ECC
1.35
4
1333
RDIMM
2
x8
Advanced ECC
1.35
4
1600
RDIMM
2
x8
Advanced ECC
1.5
4
1333
RDIMM
1
x4
All modes
1.35
4
1333
RDIMM
2
x8
Advanced ECC
1.35
8
1333
RDIMM
2
x4
All modes
1.35
8
1333
RDIMM
2
x4
All modes
1.35
8
1600
RDIMM
2
x4
All modes
1.5
16
1066
RDIMM
4
x4
All modes
1.35
16
1600
RDIMM
2
x4
All modes
1.5
16
1333
RDIMM
2
x4
All modes
1.35
32
1333
LRDIMM
4
x4
All modes
1.35
32
1333
RDIMM
4
x4
All modes
1.35
Flexible memory configurations are supported on the M820, ranging from capacities of 2GB to
1.5TB. The M820 supports up to 12 DIMMs per processor (up to 48 DIMMs in a four-processor
configuration). Each processor has 4 memory channels, with each channel supporting up to 3
DIMMs.
The M820 supports a flexible memory configuration, according to the following basic rules:
Speed: If DIMMs of different speeds are mixed, all channels across all processors operate at the
slowest DIMM’s common frequency.
DIMM type: Only one type of DIMM is allowed per system: RDIMM or LRDIMM. These types
cannot be mixed.
The following additional memory population guidelines apply to the M820:
Up to two quad-rank (QR) DIMMs and up to three dual-rank (DR) or single-rank (SR) DIMMs may
be populated per channel. Although an LRDIMM is physically a QR DIMM, logic on the LRDIMM
can make it appear as a DR DIMM to the system, allowing up to three LDRIMMs per channel.
DIMMs must be installed in each channel, starting with the DIMM farthest from the processor.
DIMMs should be installed with largest rank count to smallest. For example, if DR DIMMS are
mixed with SR DIMMs, DR DIMMS should be placed in the lowest DIMM slots, followed by the SR
DIMMs.
For more information on memory configuration and population, see the Dell PowerEdge M820
Systems Owner’s Manual on Support.Dell.com/Manuals.

19 PowerEdge M820 Technical Guide
Memory speeds of 1600MT/s, 1333MT/s, 1066MT/s, and 800MT/s are supported on the M820,
depending on the DIMM types installed and the configuration. All memory on all processors and
channels run at the same speed and voltage. By default, the system runs at the highest speed for the
channel with the lowest DIMM voltage and speed. The operating speed of the memory is also
determined by the maximum speed supported by the processor, the speed settings in the BIOS, and
the operating voltage of the system.
Table 8 lists the memory configuration and performance details for the M820, based on the
population of the number and type of DIMMs per memory channel.
DIMM
type
DIMM 0
DIMM 1
DIMM 2
Number
of
DIMMs
Speed (MT/s)
800
1066
1333
1600
RDIMM
SR
1
∞
∞
∞
∞
DR
1
∞
∞
∞
∞
QR
1
∞
∞
SR
SR
2
∞
∞
∞
∞
SR
DR
2
∞
∞
∞
DR
DR
2
∞
∞
∞
∞
QR
SR
2
∞
QR
DR
2
∞
QR
QR
2
∞
SR
SR
SR
3
∞
∞
SR
SR
DR
3
∞
∞
SR
DR
DR
3
∞
∞
DR
DR
DR
3
∞
∞
QR
1
∞
∞
QR
QR
2
∞
∞
QR
QR
QR
3
∞

20 PowerEdge M820 Technical Guide
Reliability, availability, and serviceability (RAS) features help keep the system online and operational
without significant impact to performance, and can decrease data loss and crashing due to errors.
RAS aids in rapid, accurate diagnosis of faults that require service. Table 9 describes the memory RAS
features supported on the M820.
Feature
Description
Dense configuration
optimized profile
Increased memory reliability can be a result from this selectable platform profile
that adjusts parameters to reduce faults regarding refresh rates, speed,
temperature and voltage.
Memory demand and
patrol scrubbing
Demand scrubbing is the ability to write corrected data back to the memory once
a correctable error is detected on a read transaction. Patrol scrubbing proactively
searches the system memory, repairing correctable errors.
Recovery from single
DRAM device failure
(SDDC)
Recovery from Single DRAM Device Failure (SDDC) provides error checking and
correction that protects against any single memory chip failure as well as multi-bit
errors from any portion of a single memory chip.
Failed DIMM isolation
This feature provides the ability to identify a specific failing DIMM channel pair,
thereby enabling the user to replace only the failed DIMM pair.
Memory mirroring:
intra-socket
Memory mirroring is a method of keeping a duplicate (secondary or mirrored)
copy of the contents of memory as a redundant backup for use if the primary
memory fails. The mirrored copy of the memory is stored in memory of the same
processor socket.
Memory address parity
protection
This feature provides the ability to detect transient errors on the address lines of
the DDR channel.
Memory sparing (rank)
Memory sparing allocates one rank per channel as a spare. If excessive correctable
errors occur in a rank or channel, they are moved to the spare area while the
operating system is running to prevent the errors from causing an uncorrectable
failure.
Memory thermal
throttling
This feature helps to optimize power/performance and can also be used to
prevent DIMMs from overheating.
For information on memory mirroring and sparing configurations, see the Dell PowerEdge M820
Systems Owner’s Manual on Support.Dell.com/Manuals. Memory RAID is not supported.