PERC-H840: Dell PERC H840 12Gb/s SAS External RAID Controller with 8GB NV Cache
Also listed as: 405-AAOX, 0T3GHR, T3GHR · made by Broadcom
The Dell PERC-H840 is a Dell PERC H840 12Gb/s SAS External RAID Controller with 8GB NV Cache providing hardware RAID management and cache protection for storage volumes in Dell PowerEdge R740, R640, R750, R650 servers.
Specifications
| Part number | PERC-H840 |
|---|---|
| Brand | Dell |
| Made by | Broadcom |
| Type | RAID controllers |
| Other numbers | 405-AAOX, 0T3GHR, T3GHR |
| Status | current |
| Interface | PCIe 3.0 x8 |
| Data transfer rate | 12Gb/s SAS per port |
| Cache size mb | 8,192 |
| Raid levels | RAID 0, 1, 5, 6, 10, 50, 60 |
| Form factor | PCIe low-profile adapter (dual external mini-SAS HD SFF-8644 ports) |
About the PERC-H840
The Dell PERC-H840 is a Dell PERC H840 12Gb/s SAS External RAID Controller with 8GB NV Cache designed to manage enterprise RAID storage across SAS, SATA, and NVMe drives. Engineered with dedicated I/O processing silicon and onboard cache, the PERC-H840 executes hardware RAID levels 0, 1, 5, 6, 10, 50, and 60 with battery-backed or flash-backed cache protection. In Dell's server line-up, PERC-H840 ensures data availability and write caching for mission-critical storage volumes.
Compatibility
The PERC-H840 controller installs into dedicated storage slots or PCIe risers on Dell PowerEdge servers including R740, R640, R750, R650. The PERC-H840 interfaces with internal hot-plug drive backplanes via SAS or SlimSAS cabling and manages drives mounted in appropriate chassis caddies. Supported operating systems on the PERC-H840 include VMware ESXi, Windows Server, and Linux distributions with Dell PERC driver support.
How to identify a genuine unit
Authentic Dell PERC-H840 PERC controllers display a serialized label showing DP/N 405-AAOX, PERC branding, and Broadcom or LSI manufacturing markings. Within iDRAC under Storage Controllers, the PERC-H840 card enumerates with full firmware revision, battery or supercapacitor health telemetry, and connected virtual disk details.
Buying used
When sourcing a pre-owned PERC-H840, inspect the card PCB for damaged surface passives or warped heatsink assemblies. Test the backup battery or supercapacitor pack on the PERC-H840 to ensure it holds a charge and reports healthy cache protection in iDRAC. Verify that all PERC-H840 SAS/NVMe physical channels detect attached drives without bus timeout errors.
Fits these models
- Dell PowerEdge R740
- Dell PowerEdge R640
- Dell PowerEdge R750
- Dell PowerEdge R650
- Dell PowerVault MD1400
- Dell PowerVault MD1420
Equivalent part numbers
- Broadcom MegaRAID 9480-8e Broadcom SAS3516 external ROC equivalent
FAQ
What enclosures connect to the PERC H840?
Dell PowerVault MD1400 (12x 3.5-inch) and MD1420 (24x 2.5-inch) 12Gb/s SAS enclosures.
How many external drives can the H840 manage?
Up to 192 drives across up to eight daisy-chained PowerVault enclosures.
Buying or selling PERC-H840?
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 RAID Controller H840 User Guide, checked 2026-10-27