The PowerEdge R670 is Dell's 1U two-socket server for Intel Xeon 6, and it will put up to 288 E-cores, 32 DDR5 slots and twenty EDSFF NVMe bays into a single rack unit. That density is the appeal, and it is also the catch: in one rack unit the choices interlock, so the front drive layout you pick decides which processors can stay on air, the core type you pick decides how much memory you can address and which operating systems Dell lists, and the storage format rules out the SAS disks an older estate is full of. This guide walks the decisions in the order they constrain each other, using the figures Dell publishes in its R670 technical guide.
View the data behind this chart
| Layer | Detail |
|---|---|
| OCP 3.0 networking | two bays, front or rear I/O |
| 20 x E3.S Gen5 | EDSFF only, no SAS or HDD |
| 2 x Xeon 6 | to 288 E-cores or 172 P-cores |
| 32 DDR5 slots | 8 channels per CPU, 6400 MT/s |
| BOSS-N1 boot | mirrored, outside the bays |
What the R670 is
The R670 is the Xeon 6 machine that follows the R660 in Dell's 1U rack line, and it keeps the shape its predecessor established: two sockets, 32 DDR5 RDIMM slots at eight channels per processor, and a front bay row for flash. What changes is the scale of each. Dell lists 23 Xeon 6 processors for it, memory is rated at 6400 MT/s where the R660 stopped at 5600, the front takes as many as twenty EDSFF E3.S Gen5 bays against the R660's sixteen, PCIe becomes three x16 Gen5 slots, networking moves to two OCP NIC 3.0 bays, and management steps to iDRAC10.
It is worth being precise about the socket count, because the 17G line contains both answers in 1U: the R670 is the two-socket machine, and the single-socket 1U Xeon 6 server is the PowerEdge R470, with one processor and sixteen DIMM slots. If your sizing rests on how many CPUs the box holds, read it off the model number carefully. The full documented limits for the R670 sit on our R670 data sheet; this page is about which of those options you should actually choose, and the generational step itself is covered in the 16G to 17G upgrade guide.
E-cores or P-cores: the fork that gates everything else
Dell's 23 processors split into two families that behave like different platforms. Six are 6700E E-core parts, 64 to 144 single-threaded cores at 205 to 330 W; seventeen are 6700P and 6500P P-core parts, 8 to 86 two-threaded cores at 150 to 350 W. Two sockets of the largest E-core part is 288 cores in one rack unit, and two of the largest P-core part is 172. Both sockets must carry the same model, so this is a decision you make once for the chassis.
The catch is that the E-core parts carry restrictions that have nothing to do with cores. They accept only 32 GB and 64 GB memory modules and address 1 TB per socket, which caps an E-core R670 at 2 TB of memory however many slots are free, and Dell lists Windows Server with Hyper-V for P-core processors only. CXL 2.0 memory expansion is likewise P-core only. So thread-dense container and microservice fleets suit E-cores, while anything that needs large memory, Windows Server or per-core speed belongs on P-cores — the wider platform context is in Intel Xeon 6 for UK server buyers.
- •E-core: 64–144 cores per socket, 32/64 GB modules only, 1 TB per socket, no Windows Server listed
- •P-core: 8–86 cores per socket, all six module sizes, 4 TB per socket, Windows Server and CXL both listed
- •8 TB total needs 32 × 256 GB on P-cores and runs at 5200 MT/s, two modules per channel
- •The largest build that holds the full 6400 MT/s is 16 × 128 GB — 2 TB, one module per channel
- •Mixing processor models is not supported, so both sockets commit to the same family
In 1U the front layout decides your cooling
This is the constraint that surprises people, and it is the one worth settling first. In a single rack unit the drive front and the processor thermals are the same decision, because a denser bay row leaves less air for the heatsinks behind it. Dell's thermal tables keep the 350 W 6767P and 6787P on air only with the lighter fronts; with the ten-bay 2.5-inch, sixteen-bay E3.S or twenty-bay E3.S fronts those parts require Direct Liquid Cooling. The 330 W parts need liquid with the twenty-bay front. Dell notes that liquid cooling removes the thermal restrictions for every processor in the list.
Accelerators sit under the same rule. The NVIDIA L4 is the GPU Dell's thermal tables name, and it is held to a 30°C inlet with the twenty-bay E3.S fronts rather than the 35°C allowed in lighter layouts. The practical reading is that a maximum-core, maximum-bay, air-cooled R670 is not a configuration that exists: pick two of the three. If you are weighing the liquid question across a room rather than one server, air versus liquid cooling covers it, and our rack space and power density planner models what a row of these draws.
EDSFF-only storage: there is no SAS here
The R670's storage list is the sharpest break from the server it replaces, and it catches migrations. Dell's drive list for it contains no SAS drives, no hard disks and no 3.5-inch bays at all: it is NVMe plus 2.5-inch SATA SSDs, and the SATA option stops at ten bays. Its native format is EDSFF E3.S, with up to twenty Gen5 NVMe bays at the front and two more at the rear, and Dell's comparison table quotes up to 1228.8 TB raw across the twenty front bays against 204.8 TB on the R660's sixteen. If your current 1U hosts are full of SAS disks, those disks do not move into this chassis.
The controller and boot arrangement follows from that. Internal RAID comes from front-mounted PERC H965i, H365i or H975i controllers, there is no software RAID option, and ESXi supports the H975i from version 9.0 — worth checking against your hypervisor version before you order. Boot stays out of the data bays: a BOSS-N1 DC-MHS module mirrors two M.2 NVMe SSDs in RAID 1, which is the arrangement a production host should want anyway.
Front I/O or rear I/O
The R670 is offered with its I/O at either end of the chassis, and this is a genuine operational choice rather than a cosmetic one. The rear-I/O build is conventional, with networking cabled in the hot aisle. The front-I/O build moves the two OCP bays, the BOSS boot module, a serial port and an iDRAC port to the cold-aisle face; while that front iDRAC port is connected, the rear one switches off automatically. Paired with Dell's blind-mate power rails, a front-I/O server can be cabled, powered and pulled without anyone working behind the rack.
The costs are physical, so check them against the room before choosing. A front-I/O chassis cannot take a bezel and is 829.44 mm deep against 816.92 mm with a bezel for the rear-I/O version, which door clearance may or may not allow. And on rear-I/O builds, network cards of 25 Gb and above must use DAC cabling or active optics rated to 85°C, because of how hot the air leaving a 1U chassis is.
Where the R670 runs out
Three limits send you to a different model. Accelerators are capped at three single-width cards of 75 W, so any double-wide GPU means the 2U R770, which shares the R670's processor list and takes two cards of up to 450 W. Drive count beyond twenty-two NVMe bays, or any requirement for 3.5-inch capacity disks, also means stepping up or out of this family.
The third is socket count, in the other direction. If a workload genuinely fits one CPU and you are paying per-core licences, the second socket is cost you do not need — and the right machine is the single-socket R470, not a half-populated R670. One Xeon 6 now carries enough cores, memory channels and Gen5 lanes that this is a real option rather than a compromise, which is the trade-off we work through in single-socket versus dual-socket servers.
Putting it together
Spec an R670 in this order: core family first, because it gates memory and operating system; then the front bay layout, because it gates processor TDP and whether you need liquid; then I/O orientation against the rack you actually have. Keep boot on a mirrored BOSS-N1 and the usual production baseline of dual power, redundant fans and iDRAC out-of-band management. Build the configuration and request a quote in our Dell server configurator, compare it with the generation it replaces in the R660 buyer's guide, and see the wider range on our Dell servers hub.