The R6625 packs two 4th Generation AMD EPYC 9004 processors and 24 DDR5 slots into one rack unit, for up to 256 cores and 6 TB. Dell aims it at databases, data warehousing, e-commerce and HPC. This page lays out everything its guide documents, and how the 1U cooling tables decide which processors, memory sizes and fronts can be combined.
Our read of Dell’s documentation: where the R6625 is strong, and the limits worth knowing before you spec one.
Strengths
+Two sockets in one rack unit: a pair of 128-core 9754s gives 256 cores, and Dell rates them for air at 30°C with the 8 × 2.5-inch NVMe front or no backplane.
+Twenty-four DDR5 slots across two twelve-channel processors, for up to 6 TB — twice the one-socket R6615 in the same height.
+A full processor table: default TDP, cTDP range, base clock, threads and L3 for all 19 models, including the 1,152 MB-cache 9684X.
+Up to twelve direct-attached 2.5-inch NVMe drives (ten front, two rear) or sixteen EDSFF E3.S at the front.
+Dell’s liquid-cooling note removes every processor restriction for DLC builds.
Watch-outs
!On air the 9554 is marked N/A in every layout, and the table has no rows at all for the 9684X, 9384X and 9184X.
!Parts of 320 W and above are N/A on air with the 4 × 3.5-inch, 10 × 2.5-inch and 16 × E3.S fronts.
!The 4 × 3.5-inch chassis cannot take 128 GB or 256 GB modules, which holds it to 2,304 GB (24 × 96 GB).
!A one-processor build has a single PCIe slot (riser configuration 7) and cannot use Direct Liquid Cooling.
!GPU support is two 75 W single-wide cards in the technical guide but three in Dell’s spec sheet, and no models are named in either.
Processors19 SKUs
Cores / CPU16–128
DIMM slots24
Drive layouts14
Max bays16
PSU options7 · to 1,800 W
02 — Processors
19 supported processors, mapped
Dell lists 19 EPYC 9004 processors for the R6625, from 16-core parts (9124, 9174F, 9184X) to the 128-core 9754, at 200 W to 360 W default TDP with cTDP ranges reaching 400 W. The chart plots each at its default TDP; in this 1U chassis the front and the cooling method, not the socket, settle which of them a build can use.
Processor landscape — cores × TDP
19 SKUs · 1 family
AMD EPYC 9004 19Bubble size = L3 cache · hover a bubble for the full SKU
Processor explorer
filter · sort · compare
Processor
Cores / threads
Base
L3 cache
TDP
W / core
Memory
AMD EPYC 9754
128 / 256
2.25 GHz
256 MB
360 W
2.8
DDR5-4800
AMD EPYC 9734
112 / 224
2.2 GHz
256 MB
340 W
3.0
DDR5-4800
AMD EPYC 9654
96 / 192
2.4 GHz
384 MB
360 W
3.8
DDR5-4800
AMD EPYC 9684X
96 / 192
2.55 GHz
1152 MB
320 W
3.3
DDR5-4800
AMD EPYC 9634
84 / 168
2.25 GHz
384 MB
290 W
3.5
DDR5-4800
AMD EPYC 9554
64 / 128
3.1 GHz
256 MB
360 W
5.6
DDR5-4800
AMD EPYC 9534
64 / 128
2.45 GHz
256 MB
280 W
4.4
DDR5-4800
AMD EPYC 9474F
48 / 96
3.6 GHz
256 MB
360 W
7.5
DDR5-4800
AMD EPYC 9454
48 / 96
2.75 GHz
256 MB
290 W
6.0
DDR5-4800
AMD EPYC 9384X
32 / 64
3.1 GHz
768 MB
320 W
10.0
DDR5-4800
AMD EPYC 9374F
32 / 64
3.85 GHz
256 MB
320 W
10.0
DDR5-4800
AMD EPYC 9354
32 / 64
3.25 GHz
256 MB
280 W
8.8
DDR5-4800
AMD EPYC 9334
32 / 64
2.7 GHz
128 MB
210 W
6.6
DDR5-4800
AMD EPYC 9274F
24 / 48
4.05 GHz
256 MB
320 W
13.3
DDR5-4800
AMD EPYC 9254
24 / 48
2.9 GHz
128 MB
200 W
8.3
DDR5-4800
AMD EPYC 9224
24 / 48
2.5 GHz
384 MB
200 W
8.3
DDR5-4800
AMD EPYC 9184X
16 / 32
3.55 GHz
768 MB
320 W
20.0
DDR5-4800
AMD EPYC 9174F
16 / 32
4.1 GHz
256 MB
320 W
20.0
DDR5-4800
AMD EPYC 9124
16 / 32
3 GHz
64 MB
200 W
12.5
DDR5-4800
Air-cooled, the 300 W-class parts (9634, 9534, 9454, 9354) hold a 35°C rating only with the 8 × 2.5-inch NVMe front or no backplane; the other fronts drop them to 30°C.
The air table shows the 9554 as N/A everywhere and omits the 9684X, 9384X and 9184X; Dell states that liquid cooling carries no processor restrictions.
A one-processor system needs three dual-fan modules and a two-processor system four; Direct Liquid Cooling is not offered for single-processor builds.
Table 3 gives the 9684X a 320 W default TDP, while Dell’s R7615 and R7625 guides list it at 400 W.
03 — Memory
24 DIMM slots, 12 per processor
Twenty-four DDR5 RDIMM slots, twelve wired to each processor with one module per channel. The DIMM tables span 4800, 5600 and 6400 MT/s parts, and Dell’s notes clock every one of them to the processors’ 4800 MT/s ceiling.
Capacity with every slot filled
by DIMM size
Rated memory speed
from the processor table
Processor family
Up to
AMD EPYC 9004
4800 MT/s
6 TB means 24 × 256 GB. Dell also lists 3DS DDR5 RDIMMs with ECC for this platform.
The memory thermal table marks 128 GB and 256 GB modules N/A in the 4 × 3.5-inch chassis, leaving 96 GB as the largest there — 2,304 GB across 24 slots.
On air, empty slots need DIMM blanks once processor power passes 240 W; liquid-cooled systems skip the blanks.
Table 5 prints a dual-rank 128 GB module at 5600 MT/s, against the guide’s note that every DIMM is clocked to 4800 MT/s; this page uses 4800 MT/s as the running speed.
04 — Storage
14 drive-bay layouts, up to 16 bays
The 1U front can be diskless or carry four 3.5-inch, eight or ten 2.5-inch, or fourteen or sixteen EDSFF E3.S drives. A rear 2.5-inch pair is possible with one riser configuration.
Headline layouts
front panel view
Front panel
Sixteen EDSFF E3.S bays: printed as “G5 Ortho” when direct-attached on S160, or “G4 Ortho” with two H755N or H965i front PERCs for RAID.
PERC H755 — RAID. Premium Performance tier, PERC 11; front PERC
PERC H755N — RAID. Premium Performance tier, PERC 11 NVMe; front PERC (2 x for 14/16 x E3.S G4)
BOSS-N1 — boot
IDSDM — boot
All 10 controllers and 2 boot options
PERC H965i — RAID. Premium Performance tier, PERC 12 (Harpoon-based) internal; front PERC (2 x for 14/16 x E3.S G4)
PERC H965e — RAID. Premium Performance tier, PERC 12 external
Rear drives require riser configuration 5 (R3P), which leaves one low-profile slot, and an air-cooled system then needs the rear drive shroud.
The storage matrix is headed “15G Storage front” and names HBA345, H345 and H745 on its SAS/SATA rows — parts absent from the guide’s own controller tables, which list the HBA355i, H355, H755, H755N and H965 family.
Table 2 lists two rear E3.S bays (15.36 TB), but the storage matrix has no row for them.
A diskless build must boot from BOSS-N1 or IDSDM. External expansion is to ME5-series JBODs, USB tape or a NAS software stack.
Every documented layout
14 with drive bays
2.5-inch3.5-inchEDSFF (E1.S / E3.S)
05 — I/O & networking
PCIe and networking
Accelerators are a minor option on this server. The R6625 technical guide allows two single-wide 75 W GPUs and names no models; Dell’s R6625 spec sheet lists three. Two single-wide 75 W cards per the technical guide, three per the spec sheet; neither document names a GPU model or prints a GPU thermal table.
I/O topology
2 sockets
The two processors talk over xGMI, and each drives its own share of the slots. In 1U that becomes three x16 slots at most, all half-length, plus an OCP 3.0 bay on the system board.
Dell DPU via Management Interface Card (MIC) 2 x 25 GbE (optional)
2 × 25GbE
PCIe
Dell DPU via Management Interface Card (MIC) 2 x 100 GbE (optional)
2 × 100GbE
PCIe
In riser configuration 1, slot 1 belongs to processor 1 and slots 2 and 3 to processor 2; the one-processor layout (configuration 7, R2A) has slot 1 only.
Dell’s card list gives each OCP card a maximum PCIe width — x16 for six of the fourteen, x8 or x4 for the rest — but the board slot runs at x8 unless the OCP cable is fitted.
Genoa integrates up to 128 PCIe 5.0 lanes per Dell’s processor notes; the guide does not break down how many reach the slots in a two-socket system.
Serial is an option on the standard rear I/O board.
06 — Power & cooling
7 power supplies, 800–1,800 W
Up to two hot-plug 60 mm supplies in a 1+1 pair. The AC range runs from 800 W Platinum to 1800 W Titanium. Two special-feed units complete the list: one 1400 W model accepts 277 V AC or 336 V DC, the other takes a −48 to −60 V DC telco feed at 1100 W.
AC277 VAC / HVDC−48 V DC
On a 100–120 V feed the 1100 W and both 1400 W AC units give 1050 W; the 800 W unit keeps its full rating and the 1800 W has none at low line.
Dell does not list a 700 W supply for the R6625; the smallest is 800 W Platinum.
Supplies should match: at POST the larger of two unequal units is used and a warning is raised, and a hot-added unit of another wattage is not enabled.
Table 33 labels the 1800 W unit Platinum, while the guide’s other tables call it Titanium.
07 — Management, security & OS
Run it, secure it, choose the OS
Management
iDRAC9 (Express default on 600-series; Enterprise and Datacenter licences)
iDRAC Direct micro-USB at the front
iDRAC RESTful API with Redfish
iDRAC Service Module
Quick Sync 2 wireless module
OpenManage Enterprise with Power Manager, Services and Update Manager
OpenManage Mobile
Integrations: BMC TrueSight, Microsoft System Center, ServiceNow, Ansible, Terraform, VMware vCenter and vRealize Operations
Security
AMD SEV and SME
SEV-SNP (AMD Infinity Guard)
Silicon Root of Trust
Cryptographically signed firmware
Secure Boot
Secured Component Verification
Data at Rest Encryption with self-encrypting drives
System Lockdown (iDRAC9 Enterprise or Datacenter)
Secure Erase
TPM 2.0 FIPS, CC-TCG certified; TPM 2.0 China NationZ
Operating systems
Canonical Ubuntu Server LTS
Microsoft Windows Server with Hyper-V
Red Hat Enterprise Linux
SUSE Linux Enterprise Server
VMware vSAN / ESXi
Citrix XenServer
08 — Compare
R6525 → R6625 → R6725
The R6625’s guide compares it with the R6525, and the R6725 guide compares it with the EPYC 9005 successor. * Dell’s R6725 table lists the R6625 at 772.13 mm and 20.2 kg; the figures shown come from the R6625’s own guide.
Two sockets in 1U is what separates the R6625 from its one-socket twin, the R6615. The 2U R7625 and R7615 draw on the same EPYC 9004 line-up with more room for drives and cards, and the EPYC 9005 R6725 succeeds it; the Xeon R660 is the Intel equivalent in 1U.
This modelSiblings and successorEach value from that model’s own verified spec file · bars scale per column
Four two-socket builds for the 1U R6625, each inside the air-cooling limits Dell prints for its front. All parts come from the R6625 configurator list, and every build opens there for changes.
HCI & virtualisation
Twelve-NVMe hyperconverged node
Ten front and two rear NVMe drives on S160 give a vSAN-style node twelve direct-attached devices in 1U. Dell’s air table rates the 32-core 9334 (210 W default, 240 W cTDP ceiling) at 35°C with High-performance Gold fans for a ten-bay front with a rear 2.5-inch pair — a column it labels SAS — and 24 × 64 GB populates every channel on both sockets.
2 × AMD EPYC 9334 — 32 cores @ 2.7 GHz, 210 W each
24 × 64 GB DDR5 RDIMM — 1.5 TB, one per channel
12 × 3.84 TB NVMe Gen4 U.2 (10 front + 2 rear) — 46.08 TB raw, on S160
BOSS-N1 boot module (hardware RAID, 2 × M.2)
Intel 4 × 25GbE SFP28 OCP 3.0
2 × 1400 W Platinum (1+1)
VMware vSphere ESXi 9.0 · ProSupport, 3 years
Rear bays tie the server to riser configuration 5, which leaves one low-profile PCIe slot, and an air-cooled build needs the rear drive shroud.
Two 128-core 9754s are the most cores Dell lists for the R6625. Air cooling is rated only with the 8 × 2.5-inch NVMe front or no backplane, at 30°C inlet, so this build takes the eight-bay NVMe front, 24 × 64 GB and a 100GbE OCP uplink.
2 × AMD EPYC 9754 — 128 cores @ 2.25 GHz, 360 W each
24 × 64 GB DDR5 RDIMM — 1.5 TB
4 × 7.68 TB NVMe Gen4 U.2 — 30.72 TB raw
BOSS-N1 boot module (hardware RAID, 2 × M.2)
Mellanox 2 × 100GbE OCP 3.0 (x16 card)
2 × 1800 W Titanium (no low-line rating)
Red Hat Enterprise Linux 9 · ProSupport, 3 years
High-performance Gold fans and a 30°C inlet ceiling apply. Liquid cooling lifts the processor limits but is not available for single-socket systems. The OCP card runs x16 only with the OCP cable.
Sixteen E3.S drives sit behind a pair of H965i front PERCs, one of the two RAID choices (the other is the H755N) Dell’s matrix lists for the 16-bay front. The air table rates the 300 W-class, 32-core 9354 at 30°C with that front, and twenty-four 128 GB modules give 3 TB for buffer pools.
2 × AMD EPYC 9354 — 32 cores @ 3.25 GHz, 280 W each
24 × 128 GB DDR5 RDIMM — 3 TB
16 × 3.84 TB E3.S Gen5 NVMe — 61.44 TB raw
PERC H965i front RAID (Dell fits two for this front)
BOSS-N1 boot module (hardware RAID, 2 × M.2)
Broadcom 2 × 25GbE SFP28 OCP 3.0
2 × 1400 W Titanium (1+1)
Microsoft Windows Server 2025 · ProSupport Plus, 3 years
Dell prints the RAID version of the 16-bay front as “E3.S G4 Ortho” and the S160 direct-attach version as “G5 Ortho”. Processors of 320 W and above are N/A on air with the 16 × E3.S front, so a larger part here needs Direct Liquid Cooling.
Filling all 24 slots with 256 GB RDIMMs reaches the R6625’s 6 TB maximum. Dell’s memory table rates 256 GB modules at 30°C in every front except the 4 × 3.5-inch, where they are N/A, so this build pairs them with two 64-core 9534s and eight NVMe bays.
2 × AMD EPYC 9534 — 64 cores @ 2.45 GHz, 280 W each
24 × 256 GB DDR5 RDIMM — 6 TB
8 × 7.68 TB NVMe Gen4 U.2 — 61.44 TB raw
BOSS-N1 boot module (hardware RAID, 2 × M.2)
Broadcom 2 × 100GbE (Q56) OCP 3.0
2 × 1400 W Titanium (1+1)
SUSE Linux Enterprise Server · ProSupport, 5 years
With 256 GB modules fitted, the memory rather than the processors sets the 30°C inlet limit.
BOSS-N1 (hardware RAID, 2 × M.2, 480 or 960 GB) · IDSDM · internal USB
External
USB tape, NAS software stack, ME5-series JBODs
Expansion & networking
PCIe slots
Up to 3 × x16: 2 × Gen5 or 3 × Gen4 · 7 riser configurations
OCP
1 × OCP NIC 3.0 SFF, Gen4 x8 (x16 with cable)
LOM
Optional 2 × 1GbE (Broadcom BCM5720)
DPU
Management Interface Card for a Dell DPU, 2 × 25 or 2 × 100 GbE (not with the LOM)
Accelerators
GPUs
2 × single-wide 75 W (technical guide) · 3 × 75 W single-wide (spec sheet)
Power
Supplies
Two hot-plug 60 mm, 1+1 redundant
AC
800 W Platinum · 1100 W Titanium · 1400 W Platinum · 1400 W Titanium · 1800 W Titanium
277 VAC / HVDC
1400 W Titanium, 277 VAC or 336 V DC
Telco DC
1100 W, −48 to −60 V DC
Ports & video
Front
1 × USB 2.0 · 1 × VGA · iDRAC Direct (micro-AB USB)
Rear
1 × USB 2.0 · 1 × USB 3.0 · 1 × VGA (optional with DLC) · dedicated iDRAC Ethernet · optional serial
Internal
1 × USB 3.0
Video
Matrox G200, 16 MB
Environment
ASHRAE A2
10–35°C up to 900 m
ASHRAE A3
5–40°C · 35–40°C for up to 10% of annual runtime
ASHRAE A4
5–45°C · 40–45°C for up to 1% of annual runtime
Max operating altitude
3,048 m
12 — FAQ
R6625 questions, answered from the documentation
What is the maximum memory of the Dell PowerEdge R6625?
The R6625 has 24 DDR5 RDIMM slots, twelve per processor, and reaches 6 TB with 24 × 256 GB modules. The 4 × 3.5-inch chassis does not support the 128 GB or 256 GB sizes, so that build tops out at 2,304 GB with 96 GB modules.
Which processors does the R6625 support?
Nineteen EPYC 9004 models, from 16 to 128 cores at 200 W to 360 W default TDP, with cTDP up to 400 W. Dell’s table gives default TDP, cTDP range, cores, threads, L3 cache and base clock for each, and all of them run memory at up to 4800 MT/s.
Which processors can the R6625 cool with air?
The 240 W-class parts keep a 35°C rating with every front. The 300 W class holds 35°C only with the 8 × 2.5-inch NVMe front or no backplane and drops to 30°C elsewhere. Parts of 320 W and above are rated only at 30°C, and only with the 14 × E3.S (no front PERC), 8 × 2.5-inch NVMe or diskless fronts — the 9474F and 9754 lose the E3.S option too. The 9554 is N/A throughout, and the 9684X, 9384X and 9184X have no air-cooling rows.
How many drive bays does the R6625 have?
Sixteen, when the front carries EDSFF E3.S drives. For 2.5-inch storage the ceiling is twelve — ten front bays and a rear pair, all of which can run as direct-attached NVMe — and a four-bay 3.5-inch front is offered as well.
Does the R6625 support GPUs?
Dell’s technical guide lists two single-wide 75 W GPUs and names no models; its spec sheet for the same server says three. The configurator currently offers no GPU for this model, so we confirm accelerator options when we quote.
How many PCIe slots does the R6625 have, and can it run one processor?
Up to three x16 slots, two at Gen5 or three at Gen4, all half-length; riser configuration 3 gives two full-height slots instead. With one processor only riser configuration 7 applies, which leaves a single slot, and Direct Liquid Cooling is not available.
How big and heavy is the PowerEdge R6625?
Height is 42.8 mm and width 482 mm; with the bezel the R6625 measures 822.89 mm deep, or 809.05 mm without it. It weighs up to 20.4 kg with every drive fitted and 15.8 kg without drives and power supplies.
How does the R6625 differ from the R6615 and R7625?
The R6615 drops to one socket in the same 1U height, which halves memory to 12 slots and 3 TB but adds a 700 W supply option. The R7625 keeps two sockets and 24 slots in a 2U chassis, where it takes up to 24 × 2.5-inch or 32 × E3.S front drives, up to eight PCIe slots and two double-wide 300 W GPUs.
What does the R6725 change?
Dell’s R6725 guide lists two EPYC 9005 processors of up to 192 Zen5 cores, DDR5 at up to 6400 MT/s in the same 24 slots, fronts of up to 20 E3.S drives, three PCIe Gen5 slots, two OCP NIC 3.0 slots and iDRAC10.
Is the Dell PowerEdge R6625 end of life?
The R6625 technical guide publishes no end-of-sale or end-of-support date, and unlike the R7615 and R7625 guides it carries no end-of-life services section. Our end-of-life checker lists dates once Dell publishes them.
Specifications are extracted from Dell’s published documents and independently re-checked line by line. Configurations are quote-based; availability and exact options are confirmed at quotation. Last reviewed 2026-09-11.
