Home › Servers › Dell

Dell PowerEdge R840

End of saleServers2U rack
Dell PowerEdge R8402U rack24 × SFF 2.5" bays4 sockets

The Dell PowerEdge R840 is an enterprise 2U rack server powered by 4 Intel Xeon Scalable 1st Gen and 2nd Gen (up to 4 processors, 28 cores each, 205W TDP) and 48 memory slots supporting up to 6144GB DDR4-2666 / DDR4-2933 RDIMM / LRDIMM. Configured with Up to 24x 2.5-inch SAS/SATA/NVMe drives and Up to 6 PCIe Gen3 slots, the R840 delivers balanced compute and I/O density for enterprise database, hypervisor, and application workloads.

Also written as: PowerEdge R840, Dell R840, R840 4-Socket Server

Buy Dell PowerEdge R840Sell yours

Specifications

BrandDell
FamilyPowerEdge R
Form factor2U rack
ReleasedMay 2018
End of saleMay 2023
End of supportJun 2028
Cpu sockets4
Cpu platformIntel Xeon Scalable 1st Gen and 2nd Gen (up to 4 processors, 28 cores each, 205W TDP)
Memory slots48
Memory typeDDR4-2666 / DDR4-2933 RDIMM / LRDIMM
Memory max (GB)6,144
Drive baysUp to 24x 2.5-inch SAS/SATA/NVMe drives
Pcie slotsUp to 6 PCIe Gen3 slots
Gpu supportUp to 2x 300W double-wide or 4x 75W single-wide GPUs
Network onboardNetwork Daughter Card (NDC) slot; 1x 1GbE iDRAC9 port
Power supplyDual redundant hot-plug 1100W, 1600W, 2000W or 2400W Platinum

Generations

About the R840

The Dell PowerEdge R840 is an enterprise 2U rack server engineered for computing and virtualization workloads. Powered by 4 Intel Xeon Scalable 1st Gen and 2nd Gen (up to 4 processors, 28 cores each, 205W TDP) across 48 memory slots supporting up to 6144GB DDR4-2666 / DDR4-2933 RDIMM / LRDIMM, the R840 balances throughput and memory capacity. In Dell's server catalog, the R840 succeeded the POWEREDGE-R830 and was followed by the POWEREDGE-R860, positioned alongside rival systems including PROLIANT-DL560-GEN10, THINKSYSTEM-SR850.

Options and compatibility

Processor support on the R840 utilizes 4 LGA3647 (Socket P0) sockets with thermal heatsinks matching CPU power envelopes. System memory slots on the R840 require DDR4-2666 / DDR4-2933 RDIMM / LRDIMM modules, and mixing RDIMM with LRDIMM memory is not supported. The R840 chassis utilizes DXD9H (2.5-inch SFF) drive trays across its 2.5-inch drive backplane bays. Networking on the R840 uses Network Daughter Card (NDC), and expansion cards install into Up to 6 PCIe Gen3 slots risers.

How to identify it

Physical identification of the R840 is verified by the 14th-generation silver-gray brushed aluminum honeycomb bezel with the R840 badge on the front chassis ear. The pull-out information tag on the R840 control panel displays the 7-character Dell Service Tag and default login credentials. In iDRAC9, the server identifies as R840 with active firmware, slot mapping, and power telemetry.

Buying used

When evaluating a pre-owned R840, inspect the LGA3647 (Socket P0) CPU socket pins for damage and ensure retention clips are intact. Run Dell ePSA diagnostics across all 48 memory slots of the R840 to verify zero uncorrectable ECC faults under load. Verify that redundant power supplies in the R840 match in wattage and that iDRAC9 Enterprise remote console is enabled. Ensure required R840 drive caddies and bracket accessories are present.

Compatible parts

Memory

RAID controllers

Boot devices

Works together

How the Dell PowerEdge R840 connects to servers, storage and the network: 4 ways, with the parts and products on each path.

Fibre Channel SANiSCSI and NVMe/TCP over EthernetDirect-attached SASFile storage (NFS and SMB)

Fibre Channel SAN

Match the speed: 16Gb and 32Gb FC HBAs, switches and array ports work together, and each generation also runs one or two speeds below its own (a 32Gb port runs at 16Gb and 8Gb).

Adapters for the server (check the fit list)

Switches

Storage

Optics

Fibre Channel SAN: how it fits together

iSCSI and NVMe/TCP over Ethernet

Keep the speed the same at all three points: a 25GbE server, a 25GbE switch port and a 25GbE array port. Mixed speeds work but the slowest link sets the pace.

Adapters for the server (check the fit list)

iSCSI and NVMe/TCP over Ethernet: how it fits together

Direct-attached SAS

12Gb SAS uses Mini-SAS HD (SFF-8644) connectors; older 6Gb gear uses Mini-SAS (SFF-8088). Adapter cables exist, but the link runs at the slower speed.

Adapters for the server (check the fit list)

Storage

Direct-attached SAS: how it fits together

File storage (NFS and SMB)

Front-end ports face the clients; back-end ports (on scale-out systems) connect the nodes to each other and need their own switch pair.

Adapters for the server (check the fit list)

Storage

File storage (NFS and SMB): how it fits together

Plan and size it

Equivalent models from other brands

FAQ

What is the memory capacity of the PowerEdge R840?

Up to 6TB of RAM across 48 DDR4 DIMMs using 128GB LRDIMMs, or up to 15.36TB with Intel Optane Persistent Memory.

Can the R840 run with only two processors?

Yes, it can run with 2 CPUs populated, though PCIe slots and memory slots connected to CPUs 3 and 4 will be offline.

Buying or selling R840?

New, refurbished or used. Tell us the quantity and condition and we connect you with a vetted reseller in your region, usually within one working day.

Buy R840Sell yours

Sources