HP Z4 G4 Workstation
The HP Z4 G4 is the mainstream single-socket champion — Intel Xeon W-2100/W-2200 up to 18 cores, ECC memory, and dual-GPU capacity. The go-to platform for serious CAD and 3D.
HP Z4 G4 Workstation — Refurbished, Tested, Configurable
The Z4 G4 is HP’s single-socket Z-series minitower and the model that reaches our floor in the largest numbers of any Z workstation: eight DIMM slots, five usable PCIe slots and a power supply range that stretches from a quiet 465 W office build to a 1000 W four-connector graphics monster. Off-lease Z4 G4 chassis reach the second-hand market in large numbers, which is exactly why they are worth buying — parts are plentiful and the price per core is hard to beat. Everything listed here is configured and load-tested before it leaves our Michigan workshop and carries a free 1-year warranty on parts, labor and shipping.
HP Z4 G4 Specifications
| Form factor | Minitower, 4U rack equivalent — 15.2″ H × 6.65″ W × 17.5″ D, 22.4–38.2 lb depending on build |
|---|---|
| Processors | One socket: Intel Xeon W-2100 or W-2200 series, or Intel Core X-series (i7-X / i9-X) |
| Memory | 8 DIMM slots. Xeon W: registered ECC DDR4 to 512 GB at 2933/2666/2400/2133 MT/s. Core X: unbuffered non-ECC DDR4 to 256 GB |
| PCIe slots (Xeon W) | Two Gen3 x16 from the CPU, one Gen3 x8 open-ended, two Gen3 x4 from the chipset, plus a mechanical-only bulkhead slot |
| M.2 storage | Two M.2 PCIe Gen3 x4 sockets on Xeon W boards; one on Core X boards |
| Drive bays | Two internal 3.5″ (2.5″ adapters available) and two external 5.25″ |
| SATA | Six 6 Gb/s channels, on-board RAID 0/1/5/10 |
| Networking | Xeon W boards: two 1GbE ports, one supporting Intel AMT. Core X boards: one 1GbE port |
| Power supply | 465 W (no graphics power cables), 750 W (two cables) or 1000 W (up to four) — all 90% efficient |
| Options | Thunderbolt 3 add-in card, SD reader, premium front I/O with USB-C |
Source: HP Z4 G4 Workstation Tower QuickSpecs (linked below).
Two very different Z4 G4s share one chassis
HP built the Z4 G4 on two boards, and the difference decides whether a given unit fits your work:
- Xeon W builds take registered ECC memory to half a terabyte, expose both x16 slots at full width, add a second Gigabit port with AMT remote management, and support two M.2 drives. This is the version for engineering, ECC-dependent workloads and anything managed by an IT department.
- Core X builds swap ECC for cheaper unbuffered memory, drop to a single NIC and a single M.2 socket, and on some i7-X parts one x16 slot runs at x8 electrically. In exchange you get very high clocks and a lot of cores for the money — the Core i9-10980XE is an 18-core part.
Both variants appear regularly in our inventory, so read the processor in the listing title before ordering. If you are unsure which one your workload needs, ask us — we would rather talk it through than take a return.
Typical builds on this page
Our Z4 G4 shelf usually holds a spread of Xeon W-2123, W-2133 and W-2145 machines for CAD and design seats, a batch of Core i9-10980XE towers aimed at rendering and simulation, and everything from 16 GB to 256 GB of DDR4. Graphics run from an NVIDIA Quadro P620 or K2200 for 2D and light modelling up to a P4000 or a GeForce RTX 2080 Ti on the compute builds. Windows 11 Pro is the usual image; bare units without an operating system are listed when we have them. If nothing matches, choose a build-to-order chassis and specify the parts yourself.
Where it fits against the rest of the Z line
- HP Z440 — the previous single-socket generation on Xeon E5. Noticeably cheaper, but capped at 128 GB of memory.
- Z6 G4 and Z8 G4 — dual-socket Xeon Scalable towers with 12 and 24 DIMM slots respectively, for core counts the Z4 cannot reach.
- Z4 G5 — the newer chassis, if you need a more recent platform rather than the best price.
More options on the refurbished HP workstations hub. Upgrading a Z4 you already own? We stock matching ECC DDR4 modules, Xeon W processors and professional graphics cards separately.
HP Z4 G4 Documentation
HP Z4 G4 Workstation Tower QuickSpecs.pdf
HP Z4 G4 Workstation Tower Data Sheet.pdf
HP Z4 G4 Workstation Tower User Guide.pdf
HP Thunderbolt 3 PCIe Card Installation.pdf
HP Z4 G4 — Common Questions
What is the maximum RAM in an HP Z4 G4?
512 GB across eight slots on a Xeon W board, using registered ECC DDR4. A Core X board is limited to 256 GB of unbuffered non-ECC memory, and the two module types cannot be swapped between boards. Installed speed is set by the processor, so a W-2100 part will run modules at its own rated frequency regardless of what is printed on the label.
Does the Z4 G4 support two graphics cards?
Physically yes — there are two x16 slots — but the power supply decides. The 465 W unit ships with no auxiliary graphics cables at all, the 750 W with two, and the 1000 W with four. Tell us the cards you intend to run and we will fit the right supply before shipping.
When was the Z4 G4 introduced?
HP first published QuickSpecs for the platform in 2017, and kept revising the document into 2023 as newer Xeon W-2200 and Core X processors were added. That long options list is why two Z4 G4 towers of the same age can differ so much in specification.
What does a refurbished Z4 G4 cost?
Complete, tested builds on this page generally run from the mid hundreds to around two thousand dollars, driven mostly by processor, memory and graphics card. Bare build-to-order chassis start lower still. The listings below carry live pricing — for anything unusual, request a quote.
How are these machines checked before shipping?
Each unit is assembled to the ordered configuration, run under load, and verified for memory capacity, storage health and graphics output before it is boxed. Coverage afterwards is a free 1-year warranty including parts, labor and shipping, extendable to five years at checkout, with a 90-day return window on top.