Dell 0W23H8 / 08HT8T PowerEdge R640 System Board Specifications

1. Overview

The Dell 0W23H8 (with secondary/substitute manufacturing part numbers like 08HT8T) is an enterprise-class dual-socket motherboard engineered exclusively for the Dell PowerEdge R640 1U rack server. Supporting Intel’s 1st and 2nd Generation Xeon Scalable processors, this system board provides dense computing power, massive memory capacity, and versatile storage configurations ideal for high-density virtualization, cloud computing, and software-defined storage (SDS) infrastructures.

2. Technical Specifications

 Processor / CPU Architecture

• Socket Type: Dual FCLGA3647 (Socket P)

• Supported Processors: 1 or 2 Intel® Xeon® Scalable Processors (1st Gen “Skylake-SP” / 2nd Gen “Cascade Lake-SP”)

• Max Core Count: Up to 28 cores per processor socket (56 cores total per system)

• Thermal Design Power (TDP): Supports high-performance SKUs up to 165W-205W (requires high-performance cooling fans and appropriate heatsinks)

 Memory Architecture

• DIMM Slots: 24 DDR4 memory slots (12 DIMMs per CPU socket / 6 memory channels per CPU, 2 DIMMs per channel)

• Memory Type Supported: DDR4 Registered DIMMs (RDIMM), Load Reduced DIMMs (LRDIMM), and Intel Optane Persistent Memory (NVDIMM-N / PMem 100 series supported with 2nd Gen CPUs)

• Speed: Up to 2666 MT/s (1st Gen CPUs) / 2933 MT/s (2nd Gen CPUs)

• Maximum Capacity:

  • Up to 3.0 TB using 128GB LRDIMMs

  • Up to 7.68 TB when combining DDR4 DIMMs with Intel Optane Persistent Memory modules

• Error Correction: Advanced ECC, Memory Optimized, Memory Mirroring, and Rank Spare configurations available via system setup.

 Expansion & I/O Interfaces

• Network Daughter Card (rNDC) Slot: 1x Dedicated proprietary Network Daughter Card slot (allows installing a custom 4-port 1GbE, 2-port 10GbE, or 2-port 25GbE rNDC without consuming standard PCIe expansion slots)

• PCI Express Slots (Via Riser Cards): Supports up to 3x PCIe Gen3 slots depending on the chosen rear riser configuration:

  • Configuration 1: 2x x16 slots (Full Height)

  • Configuration 2: 3x x8 slots (Low Profile)

• Storage Controllers & Interfaces:

  • 1x Dedicated internal PERC slot (for H330, H730P, or H740P mini RAID controllers)

  • Onboard SATA ports for optical drives or boot devices

  • 1x Dedicated internal Dual MicroSD module slot (IDSDM) for redundant OS hypervisor boot.

 Management & Connectivity Ports

• Server Remote Management:

  • 1x Dedicated 1GbE iDRAC port (RJ-45) located on the rear I/O panel

• Rear Panel Ports:

  • 2x USB 3.0 ports

  • 1x VGA Video port

  • 1x Serial port (optional via breakout)

• Front Panel Connectors (routed via front control panel cabling):

  • 1x Dedicated iDRAC Direct micro-USB port

  • 1x USB 2.0 port

  • 1x VGA port

 Remote System Management & Firmware

• Onboard Management Processor: Integrated Dell Remote Access Controller 9 (iDRAC9) base hardware

• Management Features: Agent-free monitoring, remote power management, thermal oversight, automated deployment profiles, HTML5 virtual console, OpenManage integration, and comprehensive lifecycle log capture.

• System BIOS: Dell Enterprise UEFI with advanced Secure Boot, hardware root of trust, and silicon-based security enforcement.

3. Part Number Cross-Reference Matrix

When auditing data center components or sourcing parts for field replacement services (FRU), this system board can be tracked using the following matrix:

Dell Part Number (DP/N)	Alternative Substitute PN	Target System	Component Context
0W23H8 (W23H8)	08HT8T (8HT8T)	Dell PowerEdge R640	Main System Logic Board Unit Only

4. Key Deployment Notes for Data Center Technicians

• Form Factor Restriction: This system board features a highly customized, non-standard footprint layout with integrated rear I/O groupings specifically shaped to match the PowerEdge R640 1U server chassis. It is completely incompatible with industry-standard ATX, E-ATX, or generic rack enclosures.

• Processor Installation Precautions: FCLGA3647 sockets utilize fragile, high-density contact pins. Processors must be mounted onto the processor heatsink carrier clip before lowered directly into the socket to avoid pin misalignment or structural damage.

• Dual-Processor Scaling: Populating the second CPU socket is mandatory if your deployment requires utilizing the full complement of 24 memory DIMM slots or activating all secondary PCIe expansion slots routed through the rear riser assemblies.