Dell R740 Compatible Drives, Caddies & Backplanes

Short answer

What drives are compatible with the Dell PowerEdge R740 and R740xd? The R740 accepts 2.5-inch and 3.5-inch 12Gb/s SAS and 6Gb/s SATA drives across 8x3.5, 8x2.5, and 16x2.5 hot-plug backplanes; the R740xd adds 12x3.5 and 24x2.5 front bays, mid and rear bays, and U.2 NVMe options. Drives mount in 14G carriers: DXD9H (2.5-inch) and X7K8W (3.5-inch). Check fitment with our compatibility tool.

Every drive question about the PowerEdge R740 family comes down to three parts: the backplane your chassis shipped with, the carrier the drive rides in, and the controller behind it. This guide maps all three — verified against Dell's R740/R740xd Technical Guide and service manuals — so you can order drives, caddies, and backplane hardware that actually fit.

R740 vs. R740xd: chassis and backplane configurations

The R740 and R740xd share the same 2U, dual-socket 14G platform, but their storage subsystems are ordered as fixed chassis configurations. Dell's technical guide is explicit that a chassis cannot be reconfigured to a different backplane family after purchase without replacing the backplane, cabling, and often the controller — so identify what you have before buying drives.

The R740 is compute-oriented: front bays only, SAS/SATA only. The R740xd is the storage-optimized variant, adding 12x3.5" and 24x2.5" front backplanes, optional mid-bay and rear-bay drive cages, and NVMe-capable backplane options.

Configuration	Front bays	Mid bay	Rear bays	Interfaces	Max drives
R740 8 x 3.5"	8 x 3.5" (slots 0–7)	—	—	12Gb/s SAS, 6Gb/s SATA, NL-SAS	8
R740 8 x 2.5"	8 x 2.5"	—	—	SAS/SATA HDD and SSD	8
R740 16 x 2.5"	16 x 2.5" (slots 0–15)	—	—	SAS/SATA HDD and SSD	16
R740xd 12 x 3.5"	12 x 3.5"	Optional 4 x 3.5" (takes 2.5" drives via hybrid carrier)	Optional 2 x 3.5" or 4 x 2.5"	SAS/SATA	18 x 3.5"
R740xd 24 x 2.5" SAS/SATA	24 x 2.5"	Optional 4 x 2.5"	Optional 4 x 2.5"	SAS/SATA HDD and SSD	32 x 2.5"
R740xd 24 x 2.5" NVMe-capable	24 x 2.5" (12 SAS/SATA + 12 NVMe, or all-24 NVMe backplane)	—	—	SAS/SATA + U.2 NVMe	24 x 2.5"

Dell's service manual also lists a 3.5-inch hybrid backplane for the R740xd that supports SAS/SATA hot-plug drives alongside NVMe U.2 SSDs. Mid-bay and rear-bay cages hang off the front backplane's SAS expander, which is why they are SAS/SATA only. The fastest way to identify your configuration is bay count plus the system's service-tag build sheet.

Supported drive types and interfaces

Per the R740/R740xd Technical Guide, both systems accept hot-plug 12Gb/s SAS and 6Gb/s SATA drives; the R740xd additionally supports U.2 NVMe SSDs (Dell Express Flash) in NVMe-wired bays. Dell's qualified list at the platform's last guide revision covered:

2.5" SAS HDD: 10K from 300GB to 2.4TB; 15K from 300GB to 900GB; 7.2K NL-SAS 1TB–2TB. A workhorse example is the Seagate 1.2TB 10K SAS (ST1200MM0098), one of the most common R740 line items.
2.5" SAS SSD (12Gb/s): 400GB up to 7.68TB — for example the Samsung PM1643 3.84TB SAS SSD (MZILT3T8HBLS).
2.5" SATA SSD (6Gb/s): 120GB boot drives up to 3.84TB.
3.5" SAS/SATA HDD (7.2K): 1TB through 16TB, including SED/FIPS variants.
2.5" U.2 NVMe SSD (R740xd): Dell Express Flash drives from 375GB to 6.4TB at the guide's revision.

Two practical notes for refurbished buyers. First, Dell's published maximums (122.88TB for the R740 16x2.5" front, 192TB for the R740xd 12x3.5" front) reflect the largest drives Dell had qualified when the guide was published — the backplane itself does not enforce a capacity ceiling, and higher-capacity enterprise drives of the same interface generally work. Second, SATA drives run on any backplane and controller in the family, while SAS drives require a SAS-capable controller (PERC H330/H730P/H740P, HBA330, or 12Gb/s SAS HBA — all standard fitment on this platform). Browse tested pulls by interface and capacity in our storage catalog.

Drive caddies: 14G part numbers

Dell redesigned the drive carrier for 14th-generation PowerEdge, so 13G and older trays (R730/R720 era) do not fit an R740 — this is the single most common ordering mistake we see. The 14G carriers below are the correct hardware; the 2.5" carrier proved durable enough that Dell carried it into many 15G and 16G systems.

Part number	Form factor	Fits	Drive types	Notes
DXD9H (0DXD9H)	2.5" SFF carrier	R740 8/16 x 2.5" bays; R740xd 24 x 2.5" front plus 2.5" mid/rear bays	SAS/SATA HDD and SSD; also carries U.2 NVMe SSDs in NVMe-wired bays	Dell descriptor: ASSY,CARR,HD/SSD,2.5,14G. Accepts 7mm–15mm drive heights; screws included on most refurb kits
X7K8W (0X7K8W)	3.5" LFF carrier	R740 8 x 3.5" bays; R740xd 12 x 3.5" front plus 3.5" mid/rear bays	3.5" SAS/SATA HDD	Standard LFF tray across 14G rack and tower systems (R440/R540/R640/T440 and others)
9W8C4	2.5"-to-3.5" adapter bracket	Installs inside a 3.5" carrier	2.5" SAS/SATA HDD/SSD	Lets a 2.5" drive occupy an LFF bay; pair one bracket per X7K8W tray

A caddy is interface-agnostic sheet metal plus a latch and status-light pipe — the electrical work happens at the backplane. That means a DXD9H holding a SATA SSD and a DXD9H holding a 12Gb/s SAS drive are the same part; what matters is matching the tray generation (14G) and form factor to the bay. Refurbished drives from our catalog ship in the correct carrier on request.

NVMe on the R740xd: backplanes, extenders, and PCIe lanes

First, the boundary: the standard R740's front bays are SAS/SATA only. Dell's R740 technical specifications list SAS, SATA, and NL-SAS — no U.2 NVMe option exists for its front backplanes. NVMe on a plain R740 means PCIe add-in-card SSDs or the BOSS M.2 module (boot only). Hot-plug U.2 NVMe is an R740xd feature, and only on chassis built with an NVMe-capable backplane.

On the R740xd, NVMe bays are not driven by the PERC. Each NVMe-wired bay cables from the backplane to a PCIe extender (bridge) card seated in a riser slot, carrying PCIe lanes straight from the CPUs; one extender serves a group of four NVMe drives. Consequences worth pricing in before you buy:

You cannot convert a SAS/SATA-only chassis with just drives. Adding U.2 support requires the NVMe backplane, the extender card(s), and the correct cable set — on a used market that usually costs more than buying an R740xd already built as an NVMe config.
12-NVMe vs. 24-NVMe wiring differs. The 12 SAS/SATA + 12 NVMe hybrid backplane gives each NVMe drive a full x4 link through its extenders; the all-24 NVMe backplane multiplexes lanes through bridge cards in designated riser slots and requires both processors installed to light up all bays.
RAID for NVMe is software-defined. There is no hardware NVMe RAID controller for this platform. Dell's S140 software RAID supports NVMe PCIe SSDs (RAID 0/1/5/10, configured only through the UEFI utility, Dell-compliant drives only); most deployments instead hand NVMe to the OS — ZFS, Storage Spaces, vSAN, or mdraid.
SAS/SATA drives still work in NVMe universal bays on the hybrid backplane; the reverse is not true — an NVMe SSD in a SAS/SATA-only bay will not enumerate.

Drive mixing rules: what PERC allows

Mixing questions have two different answers depending on whether you mean the backplane or the virtual disk. Per Dell's PERC 10 (H740P) documentation:

Same backplane, different interfaces: allowed. SAS and SATA drives can coexist in one enclosure, and on hybrid R740xd backplanes SAS/SATA can coexist with NVMe.
Same virtual disk, SAS + SATA: not supported. Every member of a RAID virtual disk must share one interface.
Same virtual disk, HDD + SSD: not supported. Media types cannot mix within a VD.
Same virtual disk, different speeds: supported. Mixing 10K and 15K rpm, or 6Gb/s and 12Gb/s link rates, works within one drive type — the array simply performs at the slowest member's level.
NVMe under S140: NVMe and SATA cannot be combined in a single software-RAID virtual disk.

Practical build pattern for a 16x2.5" R740: a pair of SATA or SAS SSDs in RAID 1 for boot/metadata, a SAS SSD tier for hot data, and 10K SAS spindles for capacity — three separate virtual disks on one H740P, fully within spec.

Dell-branded vs. third-party drives on 14G: myth vs. reality

The 14G platform inherited a reputation from older generations that non-Dell hardware sends fans to 100%. The record, per Dell's own knowledge base and documentation:

Fan ramp is a PCIe-card behavior, not a drive behavior. Dell's 14G thermal logic raises fan response when it detects a third-party PCIe adapter it cannot read thermal data from. Front-bay SAS/SATA drives do not carry that penalty — a non-Dell Seagate or Samsung enterprise drive in a DXD9H does not, by itself, ramp fans. The caveat is NVMe: U.2 SSDs are PCIe devices, and unrecognized NVMe models can draw the elevated-airflow response.
iDRAC will note the drive, not block it. PERC firmware flags drives that lack Dell qualification data as non-certified in iDRAC and OpenManage logs. This is informational: the drive functions, performs, and joins virtual disks normally.
Firmware updates flow differently. Dell-branded drives (Dell PN plus firmware) update through iDRAC/Lifecycle Controller update packages; OEM-labeled drives take firmware from the drive maker's tools instead.
Blocking third-party drives outright is a myth on this platform. Unlike some competing vendors' controllers, 14G PERC does not refuse foreign drives.

For refurbished buyers, Dell-branded pulls remove the log noise and keep single-pane firmware management; OEM-equivalent drives (same mechanism, non-Dell label) typically cost less for identical specs. Both are legitimate paths — see our guide on refurbished vs. new vs. recertified for how we grade and test them.

Sourcing checklist for refurbished R740 storage

Before ordering, confirm four things:

Backplane: bay count and NVMe capability from the chassis build (service tag or physical inspection — NVMe-wired bays are labeled on the bezel-side bay numbering).
Controller: SAS drives need a PERC or SAS HBA; SATA runs on anything; NVMe needs extender cards and lanes, which also means checking your CPU population against the Dell R740 supported CPU list — the all-NVMe backplane requires both sockets filled.
Carrier: DXD9H for 2.5", X7K8W for 3.5", 9W8C4 bracket for 2.5"-in-LFF. Never reuse 13G trays.
Mixing plan: one interface and one media type per virtual disk.

If any of those four is uncertain, run the exact server and drive part numbers through our compatibility tool — it cross-references chassis configuration, backplane, and carrier before you commit to a purchase.

Last verified 16 July 2026 against Dell’s R740/R740xd owner’s manual and backplane documentation.

Frequently asked questions

Do third-party drives make R740 fans run at full speed?

No — for SAS/SATA drives. Dell's 14G elevated-fan response is triggered by third-party PCIe cards the system cannot read thermal data from, not by front-bay SAS/SATA drives. iDRAC may log a non-Dell drive as non-certified, but that is informational. The exception is U.2 NVMe: as PCIe devices, unrecognized NVMe SSDs can draw higher fan response.

Can I add U.2 NVMe drives to a standard R740?

No. The R740's front backplanes are SAS/SATA only per Dell's technical specifications. Hot-plug U.2 NVMe requires an R740xd built with an NVMe-capable backplane plus PCIe extender cards and cabling. On a plain R740, NVMe is limited to PCIe add-in-card SSDs, or the BOSS M.2 module for boot.

Can I mix SAS and SATA drives in the same R740?

In the same chassis and backplane, yes. In the same RAID virtual disk, no — PERC documentation states SAS and SATA cannot be combined within one virtual disk, and HDDs cannot mix with SSDs in one virtual disk. Create separate virtual disks per interface and media type; mixing rotational speeds or link rates within one drive type is fine.

Which drive caddy fits the R740 and R740xd?

DXD9H (0DXD9H) for all 2.5-inch bays and X7K8W (0X7K8W) for all 3.5-inch bays, front, mid, or rear. To mount a 2.5-inch drive in a 3.5-inch bay, add a 9W8C4 adapter bracket inside the X7K8W tray. These are 14G carriers; the DXD9H also carries U.2 NVMe drives in NVMe-wired R740xd bays.

Do R730 (13G) caddies fit the R740?

No. Dell changed the carrier design at 14G, so 13G-era trays from the R730/R720 do not latch into an R740 or R740xd. Going the other direction, the 14G DXD9H 2.5-inch carrier was carried forward into many 15G and 16G PowerEdge systems, so it remains useful across newer refurbished fleets.

What is the maximum drive count in an R740xd?

32 x 2.5-inch drives (24 front + 4 mid-bay + 4 rear) or 18 x 3.5-inch drives (12 front + 4 mid-bay + 2 rear), per Dell's spec sheet. Mid and rear bays are SAS/SATA only. NVMe-capable configurations top out at 24 x 2.5-inch front bays, with up to 12 or all 24 wired for U.2 NVMe depending on backplane.

Dell PowerEdge R740 / R740xd compatible drives, caddies & backplanes