HP Z4 Rack G5 Workstation

HP's single-socket Xeon W-2400/W-2500 (LGA4677, Intel W790) 1U rack workstation, the rack-mount successor to the ZCentral 4R. Supports one PCIe Gen5 x16 card in the single-slot riser (double-wide GPUs need the optional dual-slot riser), 4 DDR5 ECC DIMM slots up to 256 GB, and dual hot-swap 675 W PSUs.

Memory

Slots: 4 DDR5 RDIMM slots
Type: DDR5 ECC registered (RDIMM)
Speed: 4800 MT/s (16-256 GB kits); 5600 MT/s (128/256/512 GB kits using 128 GB DIMMs)
Max: 256 GB (4 × 64 GB) at 4800 MT/s, or 512 GB (4 × 128 GB) at 5600 MT/s

Storage

Bays: 2 external 2.5" bays + 1 external 3.5" bay (3.5" bay accepts 1 × 3.5" HDD or, with the HP 3.5" Drive Cage Adapter, 2 × M.2 drives)
SATA HDD: 1, 2, 4, 8 or 12 TB 7200 rpm 3.5" enterprise HDD (max 1 drive)
SATA SSD: not offered; PCIe M.2 modules used instead
PCIe SSD (M.2): Z Turbo 512 GB-4 TB PCIe Gen4 x4 2280 TLC, SED OPAL2 versions available
PCIe SSD carrier: HP Z Turbo Drive Dual Pro PCIe Gen4 x4 NVMe carrier (56Q86AA)
Onboard M.2: 2 × PCIe Gen4 x4 from CPU
RAID: Intel VROC NVMe Standard (RAID 0/1/10) or Premium (adds RAID 5 with write-hole closure)
Internal I/O: 3 internal USB ports, 1 internal SATA-3 port

Graphics

Integrated: None
Entry: NVIDIA RTX A400 4 GB, RTX A1000 8 GB
Mid-range: NVIDIA RTX PRO 2000 Blackwell 16 GB, RTX 2000 Ada 16 GB, RTX 2000E Ada 16 GB
High-end: NVIDIA RTX PRO 4000 Blackwell 32 GB, RTX 4000 Ada 20 GB, RTX PRO 4500 Blackwell 32 GB, RTX 4500 Ada 24 GB, RTX PRO 5000 Blackwell 48 GB, RTX 5000 Ada 32 GB, RTX 6000 Ada 48 GB, AMD Radeon Pro W7500 8 GB, AMD Radeon Pro W7600 8 GB
Ultra high-end: NVIDIA RTX PRO 6000 Max-Q Blackwell 96 GB (requires dual-slot riser and both 675 W PSUs)
Adapters: HP DisplayPort-to-HDMI, DisplayPort-to-VGA, DisplayPort-to-DVI, miniDP-to-DP

Expansion

Slot 1 (SSR): PCIe 5.0 x16 from CPU, via single-slot riser (includes single 6+2 pin aux power cable)
Slot 2 (DSR): PCIe 5.0 x16 from CPU (x8 if Slot 3 loaded), via optional dual-slot riser
Slot 3 (DSR): PCIe 5.0 x16 mechanical (x8 electrical) from CPU, via optional dual-slot riser
M.2 Slot 1: PCIe 4.0 x4 from CPU
M.2 Slot 2: PCIe 4.0 x4 from CPU
Notes: Dual-slot riser is required for double-wide graphics cards or configurations with more than one PCIe card, and adds a dual 6+2 pin aux power cable

Networking

Onboard: 1 × 1GbE RJ-45 (Intel AMT)
Optional (Flex I/O): Serial Port v3, 10GbE single port, 2.5GbE LAN single port, 1GbE Fiber LC NIC

Power

Entry: 1 × 675 W PSU
Entry Redundant: 2 × 675 W PSUs in redundant mode, 675 W usable
High-End: 2 × 675 W PSUs in aggregate mode, 1350 W total
Efficiency: 80 PLUS (report at clearesult.com/80plus)

Ports

Front (Premium, optional): Power button, headphone/mic combo, 2 × USB-A 5 Gbps, 2 × USB-C 20 Gbps (USB PD 3.0); requires both 675 W PSUs
Front (Entry): Power button, headphone/mic combo, 4 × USB-A 5 Gbps
Rear: 2 × USB 3.1 Gen1 USB-A, 1 × 1GbE RJ-45 (Intel AMT), Kensington lock slot, padlock loop
Rear optional: Flex I/O module; Z Desktop Power and Signal Interface for the HP Remote System Controller
Internal: 3 internal USB ports, 1 internal SATA-3 port

Physical

Form factor: 1U rackable workstation
Dimensions, base footprint (H×W×D): 43 × 438 × 654 mm
Dimensions, with bezel and rack brackets (H×W×D): 43 × 487 × 675 mm
Weight: Minimum 9.52 kg, standard 11.7 kg, maximum 12.1 kg (system only)
Operating temp: 5-35 °C

Management

Remote: HP Remote System Controller via Z Desktop Power and Signal Interface
ISV certifications: See HP workstation ISV certification list

Operating systems

Preinstalled: Windows 11 Pro for Workstations, Ubuntu Linux 22.04 & 24.02, HP Linux-ready
License only: Red Hat Enterprise Linux Desktop Workstation (paper license, no preinstalled OS)
Supported: Windows 11 21H2-25H2, Red Hat Enterprise Linux Workstation 8/9/10, SUSE Linux Enterprise Desktop 15, Ubuntu 20.04/22.04/24.04 LTS
Web-supported only: Windows 11 Enterprise

Processors

Intel Xeon W7-2595X
Intel Xeon W7-2575X
Intel Xeon W5-2565X
Intel Xeon W5-2555X
Intel Xeon W5-2545
Intel Xeon W3-2535
Intel Xeon W3-2525
Intel Xeon W3-2435
Intel Xeon W3-2425
Intel Xeon W3-2423