Dell PowerEdge MX840c
The Dell PowerEdge MX840c is a double-width, four-socket modular compute sled designed for the 7U PowerEdge MX7000 kinetic infrastructure platform. Powered by up to four 1st or 2nd Generation Intel Xeon Scalable processors, the MX840c provides 48 DDR4 DIMM slots supporting up to 6TB of memory and up to eight 2.5-inch NVMe/SAS drives. A single MX7000 enclosure can house up to four MX840c sleds, enabling massive 4-socket scale-up database processing (SAP HANA, Oracle) and server consolidation in a modular infrastructure. Used buyers should inspect the double-width blind-mate backplane connectors and verify all 4 CPU sockets.
Also written as: PowerEdge MX840c, Dell MX840c, MX840c 4-Socket Sled
Specifications
| Brand | Dell |
|---|---|
| Family | PowerEdge MX |
| Form factor | blade |
| Released | Sep 2018 |
| Cpu sockets | 4 |
| Cpu platform | Intel Xeon Scalable 1st Gen and 2nd Gen (up to 4 processors, 28 cores each, 205W TDP) |
| Memory slots | 48 |
| Memory type | DDR4-2666 / DDR4-2933 RDIMM / LRDIMM |
| Memory max (GB) | 6,144 |
| Drive bays | Up to 8x 2.5-inch SAS/SATA/NVMe SSDs |
| Pcie slots | 4 PCIe Gen3 mezzanine fabric slots |
| Gpu support | None supported |
| Network onboard | Quad mezzanine cards connected to MX7000 fabrics; iDRAC9 management |
| Power supply | Shared redundant power from PowerEdge MX7000 7U chassis |
Compatible parts
RAID controllers
PERC-H730P Dell PERC H730P 12Gb/s SAS 2GB NV Cache Mini Mono / PCIe RAID Controller
Boot devices
BOSS-S1 Dell Boot Optimized Storage Solution (BOSS-S1) PCIe Card with Dual M.2 SSDs
Works together
How the Dell PowerEdge MX840c connects to servers, storage and the network: 4 ways, with the parts and products on each path.
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)
540-BBUU Dell Emulex LPe31002 Dual Port 16Gb Fibre Channel Host Bus Adapter
540-BBUV Dell QLogic 2692 Dual Port 16Gb Fibre Channel Host Bus Adapter
540-BCMS Dell QLogic 2770 Single Port 32Gb Fibre Channel PCIe Adapter
540-BCMT Dell QLogic 2772 Dual Port 32Gb Fibre Channel PCIe Adapter
Switches
Dell Connectrix DS-6610B 1U rack
Dell Connectrix DS-6620B 1U rack
Dell Connectrix MDS-9148T 1U rack
Dell Connectrix DS-7720B 1U rack
Storage
Dell PowerVault ME4012 2U rack
Dell PowerVault ME4024 2U rack
Dell PowerVault ME4084 5U rack
Dell Unity XT 380F 2U rack
Dell Unity XT 380XT 2U rack
Dell Unity XT 480F 2U rack
Optics
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)
540-BBGN Dell Broadcom 57412 Dual Port 10GbE SFP+ PCIe Adapter
540-BBGO Dell Broadcom 57416 Dual Port 10GBASE-T RJ45 PCIe Adapter
540-BBGP Dell Broadcom 57416 Dual Port 10GBASE-T RJ45 OCP 3.0 Adapter
540-BBGY Dell Broadcom 57414 Dual Port 10/25GbE SFP28 PCIe Low Profile Network Adapter
Switches
Dell PowerSwitch S4112F-ON 1U rack
Dell PowerSwitch S4128F-ON 1U rack
Dell PowerSwitch S4148F-ON 1U rack
Dell PowerSwitch S5212F-ON 1U rack
Storage
- Dell PowerVault ME4012 2U rack
- Dell PowerVault ME4024 2U rack
- Dell Unity XT 380F 2U rack
- Dell Unity XT 380XT 2U rack
- Dell Unity XT 480F 2U rack
Dell Unity XT 480XT 2U rack
Optics
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)
405-AANT Dell 12Gbps SAS HBA Dual Port External PCIe Controller
405-AASU Dell HBA355e External SAS 12Gb/s Host Bus Adapter
Storage
Dell PowerEdge MX5016s blade- Dell PowerVault ME4012 2U rack
- Dell PowerVault ME4024 2U rack
- Dell PowerVault ME4084 5U rack
Dell PowerStore 7000T 2U rack
Dell PowerVault ME5012 2U rack
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)
- 540-BBGN Dell Broadcom 57412 Dual Port 10GbE SFP+ PCIe Adapter
- 540-BBGO Dell Broadcom 57416 Dual Port 10GBASE-T RJ45 PCIe Adapter
- 540-BBGP Dell Broadcom 57416 Dual Port 10GBASE-T RJ45 OCP 3.0 Adapter
- 540-BBGY Dell Broadcom 57414 Dual Port 10/25GbE SFP28 PCIe Low Profile Network Adapter
Switches
- Dell PowerSwitch S4112F-ON 1U rack
- Dell PowerSwitch S4128F-ON 1U rack
- Dell PowerSwitch S4148F-ON 1U rack
- Dell PowerSwitch S5212F-ON 1U rack
Storage
- Dell Unity XT 380F 2U rack
- Dell Unity XT 380XT 2U rack
- Dell Unity XT 480F 2U rack
- Dell Unity XT 480XT 2U rack
Dell Unity XT 680F 2U rack
Dell Unity XT 680XT 2U rack
Optics
Plan and size it
- Draw this setup in the topology planner mrplanb.com
- Add up rack power and space rack-density.com
- Virtualization storage Ledger: scored storage platforms mrplanb.com
- SAN transport and NVMe over FC for backup mrplanb.com
- Dell E-Lab Navigator (Dell interoperability) dell.com
Check compatibility with Dell
Before you buy, confirm the exact configuration against the vendor's own lists: firmware levels, operating systems, adapters and optics that Dell has tested with the Dell PowerEdge MX840c.
- Compatibility Dell E-Lab Navigator (storage and SAN interoperability) (free vendor sign-in)
- Support Dell Support: drivers, manuals and service tag lookup
Equivalent models from other brands
- HPE Synergy 660 Gen10 Compute Module · compare
- Cisco Ucs B480 M5
Buying a used MX840c: what to check
Verify all 4 CPU sockets and heatsinks are present, test memory across all 48 slots, inspect double-width blind-mate fabric connectors, and confirm iDRAC9 Enterprise licensing.
FAQ
How many MX840c sleds fit in an MX7000 chassis?
Up to four double-width MX840c compute sleds fit in a 7U PowerEdge MX7000 chassis.
What is the memory capacity of the MX840c?
Up to 6TB of RAM across 48 DDR4 DIMM slots using 128GB LRDIMMs.
Buying or selling MX840c?
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.
Sources
- Dell PowerEdge MX840c Spec Sheet, checked 2026-10-27