The R640 10-Bay NVMe is the refurbished 1U Dell PowerEdge configuration we reach for when NVMe storage performance is the primary driver of the procurement decision. The chassis ships with a backplane purpose-built for direct-attached NVMe across all ten front bays. Every drive connects to the CPU's PCIe lanes directly, which means full NVMe latency and bandwidth without the controller overhead a SAS/SATA-with-PCIe-NVMe workaround introduces. We deploy this chassis most often for VMware vSAN all-flash nodes, NVMe-oF storage targets, high-IOPS database tiers, and any environment where storage latency is a measured SLA rather than a marketing claim.

This chassis is the most specialized of the R640 variants and the one we recommend with the most specific use-case criteria: you need native NVMe in the front bays, you have a software-defined storage layer managing redundancy (vSAN, S2D, Ceph, ZFS), and your networking infrastructure can support the bandwidth this chassis generates under load. If your workload needs a mix of NVMe and SAS/SATA spinning disk in the same chassis, the 10-Bay + RFB may give you more flexibility. If hardware RAID across all storage volumes is a requirement, the 10-Bay Standard chassis with SAS SSDs and a PERC H740P is the safer architecture.

To configure a build, call 1-800-778-1545 or use the quote form below. Every refurbished unit ships under our 180-day warranty with 12+ hour burn-in testing, and volume pricing starts at 5 units.

When NVMe Is the Right Design

The NVMe chassis earns its place when one of these design patterns applies: VMware vSAN all-flash nodes (this is the chassis Dell originally optimized for vSAN ESA workloads), NVMe-oF storage targets in disaggregated storage architectures, high-IOPS database storage tiers where sub-100 microsecond latency is a measured requirement, all-flash object storage nodes in modern Ceph or MinIO clusters, or any environment where the software-defined storage layer is already in place and the bottleneck is the underlying media.

What does not belong on this chassis: hardware-RAID-required workloads (no PERC controller manages the NVMe front bays), mixed NVMe and spinning-disk architectures (use the + RFB), budget-driven deployments where SAS SSDs deliver equivalent real-world performance at lower cost, and any workload where the network infrastructure cannot keep up with NVMe bandwidth (a 10 GbE link is the bottleneck, not the storage). We will tell you directly at quote time if SAS SSDs are the better answer for your specific workload.

Storage - 10 NVMe Bays

Ten 2.5" hot-swap bays with native NVMe connectivity via the purpose-built backplane. Every front bay is a PCIe-attached NVMe slot; there is no SAS/SATA option on this backplane. The architectural implication is that drive redundancy must be handled at the software layer because the NVMe drives bypass the traditional PERC controller path entirely.

• U.2 NVMe SSDs (2.5" form factor): The standard format for this backplane. Available across a wide range of capacities from enterprise vendors (Dell, Samsung, Kioxia, Micron, Solidigm). For vSAN all-flash, capacity sizing is driven by your vSAN storage policy and failure-tolerance configuration; we work this calculation into every vSAN node quote.
• Read-intensive vs mixed-use vs write-intensive: Read-intensive NVMe drives carry the lowest cost per TB but have lower endurance ratings (typically 0.5 to 1 DWPD). Mixed-use drives (1 to 3 DWPD) are correct for vSAN cache tier, OLTP databases, and write-heavy general-purpose workloads. Write-intensive drives (3+ DWPD) are correct for sustained-write logging, financial transaction systems, and tier-1 cache. We do not quote read-intensive drives for cache-tier use; the endurance mismatch creates premature failure scenarios.
• Cache tier vs capacity tier within the same chassis: For vSAN or tiered architectures, splitting the front bays into a smaller cache-tier (high-endurance NVMe) and larger capacity-tier (read-intensive NVMe) is supported within the 10-bay layout. The disk-group geometry is a vSAN design decision we work through at quote time.

BOSS module for boot: Our standard recommendation on this chassis specifically. Dual mirrored M.2 SSDs on a dedicated PCIe card, completely separate from the NVMe data backplane. Keeps the OS off the NVMe array, simplifies failure isolation, and eliminates any performance contention between OS I/O and storage workload I/O. Pair with the Dell ReadyRails II sliding rail kit for in-rack serviceability.

Storage Controllers (NVMe Bypass Path)

NVMe drives in this chassis connect directly to the CPU's PCIe lanes and bypass the traditional RAID controller entirely. This is both the performance advantage of native NVMe and the most consequential architectural consideration on this chassis:

• No hardware RAID on NVMe front bays. Traditional PERC controllers do not manage NVMe drives on this backplane. Redundancy for NVMe volumes must be handled at the software layer (vSAN, Storage Spaces Direct, Ceph, ZFS, or a similar software-defined storage stack).
• PERC for BOSS or rear SAS/SATA only. If the configuration includes a BOSS module (it should), the BOSS card is its own hardware-RAID controller for the boot pair. If additional rear SAS/SATA storage is added, a PERC controller manages that path independently.
• HBA330 for additional SAS/SATA pass-through. If additional spinning disk or SAS SSDs are in the architecture alongside NVMe (rear bays or external JBOD), an HBA330 in a PCIe slot provides pass-through access for software-defined storage management.

The PERC family is still listed here for completeness when an auxiliary controller is part of the build:

• PERC H740P (8 GB NV cache, battery-backed): The production storage default on any SAS/SATA path adjacent to the NVMe backplane (rear bays, external JBOD, mixed-architecture build).
• PERC H730P (2 GB cache, battery-backed): Acceptable for any auxiliary SAS/SATA path where the workload is read-heavy.
• PERC H730 (1 GB cache, battery-backed): The 13th-gen-era controller Dell maintained Mini-PERC slot compatibility for on 14th gen. Appears on the secondary market frequently as a carryover from prior deployments and works in this chassis on any SAS/SATA path. Viable but generally a downgrade vs the H730P or H740P on Cascade Lake workloads. Quote when budget is the constraint and write performance is not load-bearing; otherwise step up.
• HBA330: Pass-through for software-defined storage on any auxiliary SAS/SATA path.

Processors

CPU options: Dual 1st Generation Intel Xeon Scalable (Skylake-SP, 2017) or 2nd Generation Intel Xeon Scalable (Cascade Lake-SP, 2019), socket LGA 3647 on the Intel C620-series chipset. Skylake and Cascade Lake are drop-in compatible on the same R640 motherboard. Up to 28 cores per CPU for a maximum 56 cores and 112 threads dual-socket.

Our SKU recommendations on this chassis: CPU selection matters more on NVMe workloads than on spinning-disk because NVMe drives consume CPU cycles for I/O processing that a SAS HBA would otherwise handle in dedicated hardware. Intel Xeon Gold 6230 (20 cores, 2.1 GHz base, 125W TDP) is our balanced default for vSAN all-flash nodes. Gold 6248 (20 cores, 2.5 GHz base, 150W TDP) is the right step up for vSAN clusters carrying high VM density or NVMe-oF targets serving many concurrent connections. For pure NVMe-oF storage targets where per-core clock speed matters more than core count, Gold 6244 (8 cores, 3.6 GHz base, 150W TDP) is a workload-specific pick that delivers excellent per-thread storage throughput.

Heatsink requirement on top-bin CPUs: Any CPU above 150W TDP, including the 165W Gold 6146 and 6244, requires Dell's high-performance heatsink kit and high-performance fan kit. The standard heatsink will boot the system but throttle under sustained load. NVMe workloads run CPUs harder than most spinning-disk workloads because the I/O processing is on-CPU; this configuration error shows up faster on this chassis than on the SAS/SATA variants.

Single-socket warning: A single-CPU NVMe build is supported but cuts the platform in half. With one CPU populated only 12 of the 24 DIMM slots are accessible, half the PCIe lanes are inactive, and several front NVMe bays route through the second CPU and become inaccessible. Single-socket on this chassis specifically reduces the available NVMe bay count, not just the PCIe expansion. The NVMe chassis is dual-socket by design; we do not quote single-socket NVMe builds.

Memory

Architecture: 24 DDR4 DIMM slots, 12 per CPU across 6 channels at 2 DIMMs per channel. The 6-channel Purley layout matters more on this chassis than most because the workloads that justify NVMe (vSAN with large cache, in-memory DB, high-concurrency OLTP) are memory-bandwidth-sensitive.

Supported DIMM types:

• RDIMM: Standard enterprise choice. Up to 64 GB per DIMM, 1.5 TB total at full population. Best price per gigabyte up to the 1.5 TB ceiling.
• LRDIMM: Up to 128 GB per DIMM, 3 TB total. The path past 1.5 TB without Optane. Modest latency premium over RDIMM.
• Intel Optane Persistent Memory (PMem): Cascade Lake L-series CPUs only (Gold 5215L, 6240L, 6248L, etc.). App Direct mode for persistent storage tier, Memory Mode for transparent capacity expansion. Up to 7.68 TB combined with LRDIMM. The vSAN-with-Optane-cache configurations specifically use PMem in App Direct mode and are a known NVMe-chassis workload; we walk through the cache-sizing math at quote time when this is in scope.
• NVDIMM-N: Niche persistent memory option, paired with RDIMM only. Rarely the right answer in 2026.

Memory speed by population: DDR4-2933 on Cascade Lake Gold 6200 / 5222 SKUs at 1 DPC, DDR4-2666 on other Cascade Lake SKUs and at full 2 DPC population, DDR4-2666 on all Skylake SKUs. Full 24-DIMM population on the NVMe chassis is common because the workloads that justify NVMe are bandwidth-sensitive; the full-channel bandwidth gain consistently outperforms partial population at higher clock.

vSAN memory reservation: vSAN reserves a meaningful amount of host memory for caching, deduplication, compression, and metadata. The reservation grows with the per-host capacity. Size the DIMM count to leave headroom for VMs after vSAN's reservation, not the other way around. We include this calculation in every vSAN node quote.

Mixing rules: Match ranks, capacity, and timing within a channel. We do not quote mixed configurations for production builds; matched-set DIMMs avoid subtle stability issues and make later memory expansion straightforward.

Networking and PCIe Expansion

25 GbE is the floor on this chassis. NVMe storage creates a networking requirement higher than a standard compute node. A 10 GbE link maxes out at roughly 1.2 GB/s, which a single Gen3 NVMe drive can saturate on sequential reads. Ten NVMe drives in a node can easily overrun a 10 GbE link. NDC options on this chassis:

• 2x 25 GbE SFP28: Our minimum recommendation for production NVMe workloads. Most vSAN all-flash deployments land here. Pair with 25 GbE top-of-rack switching and a dedicated vSAN network.
• 2x 25 GbE SFP28 plus add-in 100 GbE NIC: The common architecture for NVMe-oF targets and dense all-flash vSAN clusters. NDC carries management and VM traffic; the add-in NIC carries the storage fabric.
• 4x 10 GbE SFP+: Acceptable for smaller vSAN clusters with modest VM density where 25 GbE switching is not yet in place. Treat it as a transitional configuration, not a production target.
• 2x 10 GbE + 2x 1 GbE: Underspecced for this chassis. We will quote it on request but flag the network as the likely bottleneck.

PCIe lane budget awareness: Ten NVMe drives plus PCIe expansion cards share a finite PCIe lane budget. Each NVMe drive consumes 4 PCIe Gen3 lanes (x4). Ten drives at x4 is 40 lanes from the front backplane alone. The CPUs deliver 48 lanes per socket; dual-socket gives 96 lanes total before the chipset, NDC, BOSS, and PCIe slots take their share. "Ten NVMe plus every PCIe slot fully populated with x16 cards" is not always physically possible. We confirm lane allocation for every NVMe-heavy build at quote time and will tell you upfront when a desired configuration exceeds the lane budget.

PCIe expansion: Up to 3 PCIe Gen3 slots depending on riser configuration. The 10-Bay NVMe chassis preserves the full PCIe slot budget structurally (no RFB constraint), but the lane budget is the practical limit. Common builds on this chassis: 100 GbE add-in NIC for the storage fabric plus an external HBA for SAS shelves, or dual 25 GbE NICs plus a GPU for inference workloads.

GPU Support

GPU support on the NVMe chassis is constrained more by the PCIe lane budget than by the 1U thermal envelope. Ten NVMe drives plus a 100 GbE NIC plus a GPU adds up against the available lanes faster than against the available cooling. For inference workloads where a single NVIDIA T4 (single-width, low-profile, 70W, PCIe x16) coexists with an NVMe-backed inference dataset, the configuration works cleanly. Multi-GPU is not a viable architecture on this chassis.

FPGA support follows the same pattern: single-card builds are workable; multi-card configurations exceed either the lane budget or the thermal envelope. For GPU-heavy AI training workloads or any double-width GPU, the Dell PowerEdge R740 16-Bay 2.5" 2U platform is the right call. The NVMe chassis is a storage-first design; treating it as a GPU compute platform misallocates the hardware.

Management - iDRAC9 Generation

iDRAC9 Enterprise: Required for production deployment. Remote KVM, virtual media, predictive analytics, Group Manager for fleet-scale operations, Quick Sync 2, and Silicon Root of Trust. NVMe backplanes require specific BIOS settings for proper drive enumeration and PCIe bifurcation; iDRAC's remote configuration access is essential for diagnosing the common "drive does not appear in vSAN" symptom that traces back to a missed bifurcation setting.

Security baseline: Silicon Root of Trust anchors firmware verification in immutable silicon. System Lockdown mode prevents unauthorized firmware changes after deployment. TPM 2.0 module supported and recommended for any deployment with NIST 800-171, CMMC, FedRAMP, HIPAA, or PCI DSS compliance framework requirements. Storage nodes carrying production data should always have TPM enabled.

Lifecycle Controller and OpenManage Enterprise: Same Dell management plane as the rest of the R640 family. Lifecycle Controller for per-chassis firmware orchestration; OpenManage Enterprise for fleet-scale firmware compliance and configuration drift detection. NVMe drive firmware versions matter for vSAN compatibility; OpenManage tracks this across the fleet.

Power and Cooling

NVMe SSDs consume meaningfully more power than SAS/SATA HDDs, and a fully populated 10-bay NVMe chassis with dual high-core-count CPUs and full memory population draws significantly more than a compute-only node. PSU recommendations specific to this chassis:

• Light (Gold mid-tier CPUs, 4 to 6 NVMe drives, partial RAM): 2x 750W Platinum, peak draw approximately 450W
• Balanced (Gold 6230, 10 NVMe drives, full RAM): 2x 1100W Platinum, peak draw approximately 620W
• Heavy (Gold 6248, 10 NVMe drives, full RAM plus single GPU): 2x 1100W Platinum, peak draw approximately 820W
• NVMe-oF target with 100 GbE NIC and Gold 6244: 2x 1100W Platinum, peak draw approximately 750W

495W is not enough for this chassis. The entry-tier 495W PSU pairing common on the Standard 10-Bay chassis is not sufficient on the NVMe variant. A dual Gold 6230 with 24 DIMMs and 10x NVMe draws approximately 550 to 700W at peak depending on drive selection. Size up.

Thermal: Eight hot-plug redundant fans standard. NVMe drives generate sustained heat under load (more consistently than spinning disks, which idle thermally). The high-performance fan kit is strongly recommended on any NVMe-heavy configuration with Gold-tier CPUs. ASHRAE A3 (40C) extended ambient support is achievable with the high-performance fan kit but the margin is tighter on this chassis than on the SAS/SATA variants under sustained NVMe load.

Physical Specs & Platform Notes

• Form factor: 1U rack server. 42.8mm H x 434mm W x 735-760mm D depending on bezel and cable management options. Standard 19-inch rack mount with Dell ReadyRails II.
• PCIe expansion: Up to 3 PCIe Gen3 slots across the supported riser configurations. Structural slot count matches the Standard 10-Bay chassis; the practical limit is the PCIe lane budget, not the slot count.
• Parts availability: Strong. The NVMe backplane SKU is less common in the secondary market than the standard SAS/SATA backplane but Dell parts coverage remains active. PERC controllers, NDC cards, NVMe drives, BOSS modules, fan kits, and PSUs are all readily available.
• Accessories we recommend: Dell LCD bezel (P/N 521RX security bezel, 7M3F1 LCD bezel without security, 9NN24 with security; confirm part at quote time against your chassis revision), Dell ReadyRails II sliding rail kit, and the Dell cable management arm (CMA). The CMA matters on NVMe nodes specifically because in-rack drive replacement is the standard service path and the chassis must be pulled forward cleanly.
• Platform notes: NVMe bifurcation settings in BIOS must be configured correctly for drives to enumerate properly; this is the most common configuration mistake on self-built NVMe systems. CPU hot-plug is not supported (system must be powered down for CPU replacement). NDC swap requires powered-down access. Drives are hot-swap but the host's software-defined storage layer (vSAN, S2D) must be informed before pulling a drive in production.

Our Assessment

Where it excels: VMware vSAN all-flash nodes where the disk group geometry calls for native NVMe across the front bays. NVMe-oF storage targets where the chassis presents NVMe namespaces over a 25 GbE or 100 GbE fabric. High-IOPS database workloads (Oracle, SQL Server, PostgreSQL) where storage latency is a measured SLA and the team is comfortable managing the storage layer in software. All-flash Ceph or MinIO object storage nodes where the workload mix is random-read-heavy and sub-millisecond response time matters. Modern in-memory database hosts where Optane PMem extends the memory tier alongside NVMe storage.

Where to look instead: If hardware RAID across all volumes is a requirement (FedRAMP-validated configurations, compliance frameworks that mandate hardware-level redundancy, operations teams not equipped to run a software-defined storage stack), the 10-Bay Standard chassis with SAS SSDs and a PERC H740P delivers comparable IOPS for most enterprise workloads at lower acquisition cost. If your storage mix is part NVMe and part spinning disk, the 10-Bay + RFB with the NVMe-capable backplane is the flexible choice. If your workload needs PCIe Gen4 NVMe bandwidth, step up to the Dell PowerEdge R650 (15th gen). For GPU compute, the 1U envelope is the wrong chassis regardless of storage type; look at the R740 family.

Bottom line: The 10-Bay NVMe is a precision pick. It delivers exactly what a software-defined storage stack needs (native NVMe, no controller in the data path, full PCIe slot budget for fast networking) in exchange for taking hardware RAID off the table on the primary storage tier. When the workload is vSAN, NVMe-oF, or any modern SDS architecture, this is the right chassis. When the workload is general enterprise virtualization with hardware-RAID-managed local storage, the Standard 10-Bay is the simpler answer. We ask the storage-architecture question first and pick the chassis from the answer.

Where the R640 Fits in 2026

The R640 family is 2 to 3 generations behind current Dell production (R650 15th gen / R660 16th gen). The 10-Bay Standard page covers the generational ladder and support status in full. NVMe-specifically: the R650 brings PCIe Gen4 NVMe (roughly 2x per-drive sequential bandwidth) and the R660 brings PCIe Gen5 on Sapphire Rapids. For workloads where per-drive sequential bandwidth is the constraint (ML training data pipelines, large file streaming), the generational step is meaningful. For random-I/O-dominated workloads (databases, VDI, vSAN), the per-drive bandwidth advantage of Gen4 is smaller in real deployments than benchmarks suggest, and the 14th gen NVMe chassis remains a strong cost-performance pick in 2026.

Honest Limitations

• No hardware RAID on NVMe front bays. NVMe drives bypass the PERC controller entirely. Redundancy must be handled by a software-defined storage layer (vSAN, S2D, Ceph, ZFS). If your operations team is not equipped to manage an SDS stack, the hardware-RAID path on the Standard 10-Bay chassis with SAS SSDs is the safer choice.
• PCIe Gen3, not Gen4. NVMe drives are PCIe Gen3 x4 in this chassis. For workloads where per-drive sequential bandwidth matters (large file streaming, ML training data pipelines), Gen4 NVMe on the R650 delivers roughly 2x per-drive throughput.
• PCIe lane budget is finite. Ten NVMe drives at x4 plus PCIe expansion cards share a fixed lane budget. Some configurations require tradeoffs; we confirm lane allocation at quote time before any procurement decision is locked in.
• Network bandwidth is the most common bottleneck. A single Gen3 NVMe drive can saturate a 10 GbE link on sequential reads. For production vSAN or NVMe-oF deployments, 25 GbE is the floor and 100 GbE is increasingly common. If the network cannot keep up, the NVMe investment is wasted.
• NVMe drive endurance varies widely. Read-intensive NVMe drives are dramatically cheaper than mixed-use or write-intensive drives, but using them for cache-tier or write-heavy workloads creates premature failure scenarios. Drive class selection is part of every quote we issue; we assess remaining endurance via SMART data on every refurbished NVMe drive before inclusion in a configuration.
• Single-socket builds reduce usable bay count. Several front NVMe bays route through the second CPU. We do not quote single-socket NVMe builds.
• 2 DPC throttles memory speed. Full 24-DIMM population drops effective memory speed to DDR4-2666 from the 2933 MT/s peak on Cascade Lake Gold 6200 / 5222 SKUs. The full-channel bandwidth gain consistently outperforms half the channels at higher clock for memory-bandwidth-sensitive workloads.
• 14th gen, not current production. Dell's current 1U production platform is the R660. The R640 represents strong refurbished value in 2026 but is not new hardware.

Workload Fit

Where to Look Instead

• Need hardware RAID across all volumes? The R640 10-Bay 2.5" Standard Chassis with SAS SSDs and a PERC H740P delivers comparable IOPS for most enterprise workloads at lower acquisition cost.
• Need mixed NVMe and SAS/SATA in the same chassis? The R640 10-Bay + RFB with the NVMe-capable backplane gives you selective NVMe alongside SAS/SATA front bays.
• Compute-first with storage on SAN or external array? The R640 8-Bay 2.5" is the right call when local storage is minimal.
• Step up to PCIe Gen4 NVMe? The Dell PowerEdge R650 8-Bay 2.5" (15th gen, Ice Lake-SP) delivers roughly 2x per-drive Gen4 bandwidth for sequential workloads.
• Step down to 13th gen for budget? The Dell PowerEdge R630 10-Bay 2.5" is the 13th gen predecessor for budget-constrained refurbished builds; note that R630 NVMe is via PCIe expansion only, not a native front backplane.
• Pre-validated vSAN HCI node? The R640 VxRail 10-Bay is the VxRail-certified version of this chassis for VxRail cluster expansion.
• HPE-side NVMe equivalent? The HPE ProLiant DL360 Gen10 10-Bay 2.5" with the appropriate NVMe backplane is the direct counterpart on the same Intel Purley platform.
• Need 2U for more PCIe and more drives? The Dell PowerEdge R740 16-Bay 2.5" is the 2U companion to the R640; up to 16 SFF NVMe bays available with PCIe lane headroom for multi-100 GbE and GPU configurations.

Ready to Configure?

NVMe configurations require more upfront design work than standard SAS/SATA builds. Drive endurance selection, PCIe lane allocation, software storage layer compatibility, and network sizing all need to be right before hardware ships. Our account team handles this at the quote stage. Tell us your target workload (vSAN cluster size, database IOPS requirements, NVMe-oF fabric design), drive endurance tier, target memory footprint, NDC choice, and quantity. We return a fully validated configuration with formal pricing within 24 hours, including confirmed PCIe lane allocation against the NVMe bay count plus expansion cards, vSAN memory reservation math if applicable, and thermal validation on high-TDP CPU configurations. Every refurbished unit ships with the Wholesale Servers 180-day warranty and 12+ hour burn-in testing, and volume pricing starts at 5 units. Call 1-800-778-1545 or use the quote form below.