DELL R720 System Memory Guide

This article was excerpted from: Http://www.dell.com/support/article/cn/zh/cndhs1/SLN153646/zh#issue3 for personal use as a notePowerEdge R720 System Memory Guide
Directory:

1. R720 System Memory Guide
2. Min/MAX memory capacity
3. Memory Module Installation Guide/installation rules
4. Memory Mode Specific guidelines
5. removing/Installing system memory
6. General fault diagnosis of system memory
7. Using System diagnostics

Article Summary: This article describes the memory capabilities of the PowerEdge R720 server. The content includes supported memory types, installation rules, and general troubleshooting.

Problem 1:r720 system Memory Guide
Power Edge R720 supports DDR3 unbuffered ECC DIMMs (ECC Udimm), registered DIMMs (RDIMM), and reduced-load DIMMs (LRDIMM).

Power Edge R720 supports DDR3 unbuffered ECC DIMMs (ECC Udimm), registered DIMMs (RDIMM), and reduced-load DIMMs (LRDIMM).

Note:Dell supports only DIMMs with ECC. Operating memory speeds of 1600, 1333, 1066, and 800 are supported, but depend on the DIMM type, DIMM capabilities, and DIMMs installed on each channel. Supports two voltages: standard DIMM 1.5V voltage, supports speeds up to 1600, low voltage (1.35V), and supports speeds up to 1333 MHz. Supports single-row (SR), dual-column (DR), and four-column (QR) DIMMs.  Up to two QR DIMMs and three Dr or SR DIMMs can be installed per channel. The system consists of 24 memory slots, divided into two groups (12 per group), one per processor group. Each of the 12-socket components into four channels. In each channel, the release lever of the first slot is marked in white, the release lever for the second slot is black, and the third slot's release lever is marked in green ( Figure 1[English only]).


Figure 1:-Memory configuration Note:Assigning DIMMs in slots A1 to A12 to processor 1, allocating DIMMs from slots B1 to B12 to processor 2

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Issue 2: Minimum/maximum memory capacity
Minimum RAM

• 2GB with a single processor/4GB with two processors

Max RAM

• LRDIMM, Max 768GB (PowerEdge r720xd,2.5 inch HDD Configuration)
• RDIMM, Max 512GB
• UDIMM, Max 64GB

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Issue 3: Memory Module Installation Guide/
Installation rules
This system supports flexible memory configurations so that the system can be configured and run in any valid chipset architecture configuration. For best performance, here are some recommended guidelines:

• Do not mix Udimm, Rdimm and Lrdimm.

• DIMMs based on X4 and x8 dram can be mixed. For more information, see pattern-specific guidance.

• A maximum of two Udimm can be installed on a single channel.

• Up to two four-column Rdimm and up to three double-or single-column RDIMM can be installed per channel. If the four column Rdimm is installed in the first slot with a white release lever, it cannot be installed in a third DIMM slot with a green release lever in the channel.

• You can install up to three Lrdimm, regardless of the number of columns.

• The DIMM slots are mounted only on the condition that the processor is installed. For single-processor systems, slots A1 to A12 are available. For dual processor systems, slots A1 to A12 and slots B1 to B12 are available.

• First load all slots with white release tabs, then load black and green in turn.

• If the four column Rdimm is installed in the first slot with a White release tab, do not install in the third DIMM slot with the Green Release tab in the channel.

• Mount the slots in the highest column count (in the following order)-first in a slot with a white release lever, then black, green. For example, if you want to mix four-column and double-row DIMMs, install the four-column DIMM in a slot with a White release tab and install the dual-row DIMM in a slot with a black release tab.

• In a dual-processor configuration, the memory configuration of each processor must be the same. For example, if you populate socket A1 for Processor 1, the slot B1 is populated for processor 2, and so on.

• In the case of other memory installation rules, it is possible to mix memory modules of different sizes (for example, you can mix 2GB and 4GB memory modules).

• Each processor can install four DIMMs at a time (one DIMM per channel) to maximize performance.

• If memory modules of different speeds are installed, they will run at the slowest installed memory module speed, or run at a slower rate depending on the system memory configuration.

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Issue 4: Memory Mode specific guide
Each processor is assigned a four memory channel. The configuration that is allowed depends on the selected memory mode. Note:If RAS functionality is supported, DIMMs based on X4 and x8 dram can be mixed. However, all specific RAS feature guidelines must be followed. X4 DRAM-based DIMMs retain a single device data repair (SDDC) in an optimized memory (standalone channel) mode.  DIMMs based on X8 dram require advanced ECC mode for the SDDC. The following sections provide additional socket installation guides for each mode:

Advanced ECC (lockstep)The advanced ECC mode extends the SDDC from X4 DRAM-based DIMMs to X4 and x8 dram. This prevents a single DRAM chip from failing during normal operation. Memory Installation Guide:

• The memory modules must be the same size, speed, and technology.
• DIMMs installed in memory slots with white release tabs must be identical, and similar rules apply to slots with black and green release tabs. This ensures identical DIMMs are installed in pairs. For example: A1 and A2, A3 and A4, A5 and A6, etc.

Advanced ECC (lockstep/x8 SDDC) Installation:{1+2, 3+4}, {5+6, 7+8}, {9+10, 11+12} Note:Advanced ECC with mirroring is not supported. Memory optimized (standalone channel) mode
This mode only supports the SDDC for memory modules, which use the X4 device width and do not impose any specific slot installation requirements. Memory Optimized (standalone) installation:{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12} Memory Hot Standby Note:To use memory hot spares, you must enable this feature in your system settings. In this mode, one column of each channel is reserved for backup.  If you detect a permanently correctable error on a column, copy the data in that column to an alternate column, disabling the failed column. If memory hot provisioning is enabled, system memory available to the operating system is reduced by one column per channel. For example, in a dual-processor configuration with 16 4GB dual-row DIMMs, the available system memory is: 3/4 (column/channel) x16 (DIMM) X4GB = GB, not (DIMM) x4 GB = Five GB. Note: Memory Hot spares do not provide protection against multiple uncorrectable errors.
Note:Advanced Ecc/lockstep and Optimizer modes support memory hot provisioning. Memory MirroringCompared to all other modes, memory mirroring provides the strongest DIMM reliability mode and provides improved, uncorrectable, multi-bit fault protection. In a mirrored configuration, the total system memory available is half the total installed physical memory. Half of the installed memory is used to mirror the active DIMM. If an uncorrectable error occurs, the system switches to a copy of the mirror. This will ensure the SDDC and multi-bit protection. Memory Installation Guide:

• The memory modules must be the same size, speed, and technology.
• DIMMs installed in memory slots with white release tabs must be identical, and similar rules apply to slots with black and green release tabs. This ensures identical DIMMs are installed in pairs. For example: A1 and A2, A3 and A4, A5 and A6, etc.

Image installation:{1+2, 3+4}, {5+6, 7+8}, {9+10, 11+12} Note:Advanced ECC with mirroring is not supported.

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Issue 5: Removing/Installing system memory

Remove memory Module   warning : the Memory module feels hot for a period of time after power off the system. Wait for a period of time to cool the memory module before operating it. Grasp the edge of the memory module card to avoid touching the component on the memory module.   Note: Most repairs can only be performed by qualified service technicians. You can only troubleshoot and perform simple repairs based on the authorization in the product documentation, or under the guidance of an online or telephone service and support team. Damage caused by services not authorized by Dell is not covered by the warranty. Please read and follow the safety instructions included with the product. Note: to ensure proper system cooling, the memory module blank must be installed in any unused memory slots. You can remove the memory module blank only if you want to install memory in these slots.

1. Shut down the system, including all attached peripherals, and disconnect the system from the power outlet and peripheral devices.

2. To open the system.

3. Remove the cooling shroud.
   Click to view the 8 second disassembly video .

4. To locate the appropriate memory module slot.
   Note: grab only the sides of each memory module card and make sure not to touch the middle of the memory module.

5. Press down and out on the ejectors on each end of the socket until the memory module pops out of the socket ( Figure 2 ).
   
   
   Figure 2: Remove and install memory modules
   1. Memory Module
   2. Memory Module Socket ejectors (2)
   3. For alignment

6. , install the Memory module blank in the spare memory module slot to ensure proper system cooling.

7. To install the cooling shroud.

8. To shut down the system.

9. Reconnect the system to the power outlet and turn on the system and all attached peripherals.

Installing memory Modules Warning: The memory module will feel hot for a period of time after powering down the system. Wait for a period of time to cool the memory module before operating it. Grasp the edge of the memory module card to avoid touching the components on the memory module. Note:Most repairs can only be performed by qualified service technicians. You can only troubleshoot and perform simple repairs based on the authorization in the product documentation, or under the guidance of an online or telephone service and support team. Damage caused by services not authorized by Dell is not covered by the warranty. Please read and follow the safety instructions included with the product. Note:To ensure proper system cooling, a memory module blank must be installed in any unused memory slot. You can remove the memory module blank only if you want to install memory in these slots.

1. Turn off the system, including any attached peripherals, and disconnect the system from the power outlet and peripherals.

2. Open the system.

3. Remove the cooling shroud.
   Click to view the 8 second disassembly video .

4. Locate the memory module slot.

5. Press down and out on the ejectors on the memory module socket to insert the memory module into this slot. If the memory module bezel is installed in the slot, remove the bezel.
   Note: keep the removed memory module blank for future use.
   Note: just grab the sides of each memory module card and make sure not to touch the middle of the memory module.

6. Align the edge connector of the memory module with the position card lock of the memory module slot and insert the memory module into the slot.
   Note: the Memory module slot has a pair of alignment that allows you to insert the memory module into the slot in a unique direction.

7. Press the memory module down with your thumb until the socket lever latch locks into place.
   If the memory module is seated correctly in the slot, the lever on the memory module slot should be aligned with the lever on the other slots of the installed memory module.

8. Repeat steps 4 through 7 of this procedure to install the remaining memory modules.

9. Replace the cooling shroud.

10. Shut down the system.

11. Reconnect the system to the power outlet and turn on the system and all attached peripherals.

12. Press <F2> enter system settings to check the memory settings.
    The system should have changed the value to reflect the newly installed memory.

13. If the value is incorrect, one or more memory modules may not be installed correctly. Repeat steps 4 through 7 of this procedure to check to make sure that the memory modules are firmly seated in their respective slots.

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Issue 6: System memory General
Fault diagnosis
Note:Most repairs can only be performed by qualified service technicians. You can only troubleshoot and perform simple repairs based on the authorization in the product documentation, or under the guidance of an online or telephone service and support team. Damage caused by services not authorized by Dell is not covered by the warranty. Please read and follow the safety instructions included with the product.

1. If the system can run, run the appropriate diagnostic test. For diagnostic tests that are available, see Using System diagnostics. If the diagnostics indicate a failure, follow the corrective action provided by the diagnostics.

2. If the system does not work, turn off the system and attached peripherals and disconnect the system from the power supply. Wait at least 10 seconds, and then reconnect the system to the power supply.

3. Turn on the system and connected peripherals, and watch for messages on the screen. If an error message appears indicating that a particular memory module has failed, go to step 12.

4. Enter system settings and check the system memory settings. Make changes to the memory settings as needed. If the memory settings match the installed memory but still indicate a problem, go to step 12.

5. Turn off the system and attached peripherals, and disconnect the system from the power outlet.

6. Open the system.

7. Check the memory channel to make sure the memory is plugged in correctly.

8. Reseat the memory module in the appropriate slot.

9. Shut down the system.

10. Enter system settings and check the system memory settings. If the problem is not resolved, proceed to the next step.

11. Open the system.

12. If a diagnostic test or error message indicates that a particular memory module has failed, swap or replace it with a known-good memory module.

13. To troubleshoot an unspecified faulty memory module, replace the module in the first DIMM slot with a memory module of the same type and capacity. If an error message appears on the screen, this may indicate an issue with the installed DIMM type, incorrect DIMM installation, or faulty DIMMs. Follow the onscreen instructions to resolve the issue.

14. Shut down the system.

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Issue 7: Using System diagnostics
If there is a problem with your system, run the system diagnostics before calling for technical assistance. Running the system diagnostics is designed to test the system's hardware, no additional devices are required, and no data is lost. If you are unable to resolve the issue yourself, repair and support personnel can use the diagnostic test results to help you resolve the issue.

Dell Online DiagnosticsThe Dell Online Diagnostics is a set of independent diagnostic or instrumentation modules that allow diagnostic tests to run on systems in a production environment and help to maximize the uptime of your system. You can use the online diagnostics to run diagnostic tests on chassis and storage components such as hard disks, physical memory, and network interface cards [NICs]. You can use the graphical user interface (GUI) or the command line interface (CLI) to run diagnostic tests on the hardware found in online diagnostics on the system. For information about using diagnostics, see Dell Online PowerEdge under Software (software) →serviceability tools (serviceability tools) in Support.dell.com/manuals Diagnostics user ' s Guide (Dell Online PowerEdge Diagnostics). Dell Embedded System Diagnostics Note:Also known as enhanced pre-boot system Evaluation (EPSA) diagnostics. The embedded system diagnostics provides a specific set of device group or device options that allow you to:

• Run tests automatically or in interactive mode
• Repeat Test
• Show or save test results
• Run comprehensive tests to introduce additional test options to provide additional information about the faulty device
• View status information that tells you whether the test completed successfully
• Review the error messages that tell you about the problems you encountered during the test

when to use embedded system diagnosticsIf the primary component or device in the system does not function correctly, running the embedded system diagnostics may indicate that the component has failed. run the embedded system diagnosticsThe embedded system diagnostics run from the Dell life cycle controller. Note:The embedded system diagnostics are only used to test your system. Using this program to test other systems may result in invalid results or error messages.

1. Press <F11> during system boot.
2. Use the UP and DOWN ARROW keys to select the system Utilities (Systems Utility) →launch Dell Diagnostics (Start Dell Diagnostics).
   The EPSA Pre-Boot System assessment (EPSA Pre-boot Systems Evaluation) window is displayed, which lists all the devices detected in the system. The diagnostics begin to perform tests on all detected devices.

System Diagnostics Control

• configuration: Displays the configuration and status information for all detected devices:
• Result: Displays the results of all tests performed.
• System Health: provides a current overview of system performance.
• Event log: displays a timestamp-stamped log of all test results that are running on the system. This log is displayed if at least one event description is logged.
  
  For information about embedded system diagnostics, refer to Dell Enhanced Pre-Boot System Assessment User Guide in Dell.com/support/manuals (Dell enhanced pre-boot system evaluation).

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DELL R720 system memory Guide