This article provides general information regarding Dell PowerEdge servers with AMD EPYC series processors. Drivers, manuals, and specifications can be found on the product support page at dell.com/support
Table of Contents
- OS support matrix for Dell PowerEdge R6415/R7415/R7425
- Memory DIMM population guidelines
- Alignment of PCIe and memory slots
- How to find the AMD EPYC resources directly?
1. OS support matrix for Dell PowerEdge R6415, R7415, R7425
Supported operating systems for PowerEdge servers can be found on this page :
https://www.dell.com/support/contents/article/product-support/self-support-knowledgebase/enterprise-resource-center/server-operating-system-support
BIOS and UEFI installation on R6415, R7415 and R7425
The legacy BIOS boot mode is not available for Dell AMD servers. Therefore, users may only select operating systems that are UEFI-capable. Additional OS installation requirements may apply. For more information regarding OS installation on AMD servers, please read this article.
2. Memory DIMM population guidelines
Dell AMD servers support Flexible Memory Configuration, meaning memory modules can be configured and run in any valid chipset architectural configuration. Consider the following requirements and guidelines when installing memory modules:
- RDIMMs and LRDIMMs must not be mixed.
- x4 and x8 DRAM based memory modules cannot be mixed.
- Up to two RDIMMs can be populated per channel regardless of rank count.
- Up to two LRDIMMs can be populated per channel regardless of rank count.
- If memory modules with different speeds are installed, they will operate at the speed of the slowest installed memory module(s) or slower depending on the system's DIMM configuration.
- Populate memory module sockets only if a processor is installed. For single-processor systems, sockets A1 to A16 are available.
- When mixing memory modules with different capacities, populate the sockets with memory modules with the highest capacity first. For example, if you want to mix 8 GB and 16 GB memory modules, populate 16 GB memory modules in the sockets with white release tabs and 8 GB memory modules in the sockets with black release tabs.
- Memory modules of different capacities can be mixed provided other memory population rules are followed (for example, 8 GB and 16 GB memory modules can be mixed).
- Mixing of more than two memory module capacities in a system is not supported.
- Populate eight memory modules per processor (1 DIMM per channel) at a time to maximize performance.
- For optimal performance, populate one DIMM per channel with a DDR4-2666 memory module on the first slot of each memory channel. The first slot of each channel can be identified as the DIMM slot with white latches. For example, a system with 64 GB system memory capacity can be divided into 8 x 8 GB DIMM slots.
- To determine the processor's maximum supported DIMM frequency, please refer to the AMD EPYC 7000 series datasheet.
Memory specifications
- PowerEdge R6415 / R7415
- PowerEdge R7425
1. PowerEdge R6415 / R7415
The PowerEdge R6415 and R7415 system supports 16 DDR4 registered DIMM (RDIMMs) slots. Supported memory bus frequencies are 2666 MT/s, 2400 MT/s, 2133 MT/s, and 1866 MT/s.
The table below shows the memory specifications.
DIMM type |
DIMM rank |
DIMM capacity |
Minimum RAM |
Maximum RAM |
LRDIMM |
Octal rank |
128 GB* |
128 GB |
2 TB |
LRDIMM |
Quad rank |
64 GB |
64 GB |
1 TB |
RDIMM |
Single rank |
8 GB |
8 GB |
128 GB |
RDIMM |
Dual rank |
16 GB |
16 GB |
256 GB |
RDIMM |
Dual rank |
32 GB |
32 GB |
512 GB |
*- Maximum DIMM/memory capacity of 128 GB will be available at a later time.
Note: For optimal performance, populate one DIMM per channel with a DDR4-2666 memory module on the first slot of each memory channel. The first slot of each channel can be identified as the DIMM slot with white latches. For example, a system with 64 GB memory capacity can be divided into 8 x 8 GB DIMM slots.
2. PowerEdge R7425
The PowerEdge R7425 system supports up to 32 288-pin RDIMMs, and LRDIMMs with speeds of 2666 MT/s, 2400 MT/s, 2133 MT/s, and 1866 MT/s, with support for memory-optimized operation.
The table below shows the memory specifications for the R7425 system:
DIMM type |
DIMM rank |
DIMM capacity |
Single processor |
Dual processors |
Minimum RAM |
Maximum RAM |
Minimum RAM |
Maximum RAM |
LRDIMM |
Octal rank |
128 GB* |
128 GB |
2 TB |
256 GB |
4 TB |
LRDIMM |
Quad rank |
64 GB |
64 GB |
1 TB |
128 GB |
2 TB |
RDIMM |
Single rank |
8 GB |
8 GB |
128 GB |
16 GB |
256 GB |
RDIMM |
Dual rank |
16 GB |
16 GB |
256 GB |
32 GB |
512 GB |
RDIMM |
Dual rank |
32 GB |
32 GB |
512 GB |
64 GB |
1024 GB |
*- Maximum DIMM/memory capacity of 128 GB will be available at a later time.
3. Alignment of PCIe and memory slots
1 CPU - PowerEdge R6415/R7415
Expansion card riser specifications can be found in the
Dell EMC PowerEdge R6415 Installation and Service Manual ;
Dell EMC PowerEdge R7415 Installation and Service Manual
For optimal latency, populate PCIe devices in slots that are aligned to its die/Memory slots.
2 CPUs - PowerEdge R7425
Expansion card riser specifications can be found in the
Dell EMC PowerEdge R7425 Installation and Service Manual.
For optimal latency, populate PCIe devices in slots that are aligned to its die/Memory slots
4. How to find the AMD EPYC resources directly
EPYC Resources are available on the following website: https://developer.amd.com/resources/epyc-resources/
A repository of all EPYC technical documentation is listed:
- Tools, SDKs, and Libraries
- EPYC Reference Architectures
- Solution Briefs
- Specifications and Manuals
- Tuning Guides
- Ecosystem (OS and Hypervisor)
There is also a community dedicated to AMD servers at
https://community.amd.com/t5/server-gurus/ct-p/amd-server-gurus
You will find discussions and support around EPYC processors:
- Important configuration
- Tuning recommendations
- Troubleshooting information
Existing AMD EPYC public technical documentation can be found in the following locations: