The HP EliteDesk 800 G5 (2018-2019) is a business-class desktop featuring 9th generation Intel Core processors, DDR4-2666 memory support, and M.2 NVMe storage compatibility. This mid-generation model balances affordability with strong performance for office and professional workloads.
This comprehensive guide covers RAM upgrades, SSD options, and power supply specifications for the EliteDesk 800 G5 tower and small form factor models.
HP EliteDesk 800 G5 Specifications
| Specification | Detail |
|---|---|
| Release Year | 2018-2019 |
| Processor | Intel 9th Gen (Coffee Lake Refresh) — Core i3, i5, i7, Pentium |
| RAM Type | DDR4 UDIMM (standard, non-ECC) |
| RAM Speed | DDR4-2666 (native) |
| Maximum RAM | 64GB (4 × 16GB) |
| DIMM Slots | 4 (tower and SFF) |
| Slot Voltage | 1.2V standard |
| Storage | M.2 NVMe + SATA capable |
| Form Factors | SFF (Small Form Factor), Tower |
| PSU (Tower) | 240W, 320W standard |
RAM Upgrade Guide for G5
Memory Type & Official Speed
The EliteDesk 800 G5 officially supports DDR4-2666 memory, the native memory speed for 9th generation Intel processors. The motherboard uses a standard LGA1151 socket and supports four DIMM slots.
Compatibility key points:
- Use DDR4-2666 modules or slower (DDR4-2400, DDR4-2133) for guaranteed compatibility
- Faster modules (DDR4-2933, DDR4-3000) will work but throttle to DDR4-2666 automatically
- Always use 1.2V standard voltage modules; avoid 1.35V low-voltage variants
- Standard UDIMM modules only — not ECC or registered RAM
- Install modules in matching sets of two or four for optimal performance
Maximum Capacity & Configurations
The G5 supports up to 64GB of total RAM using four 16GB DDR4 modules. This doubled the G4’s capacity and made the G5 suitable for virtual machine environments and data-intensive applications.
| Configuration | Total Capacity | Module Spec | Performance Mode |
|---|---|---|---|
| Single 8GB | 8GB | 1× DDR4-2666 8GB | Single-channel (limited) |
| Pair (2×8GB) | 16GB | 2× DDR4-2666 8GB | Dual-channel (standard) |
| Quad (4×8GB) | 32GB | 4× DDR4-2666 8GB | Quad-channel (full performance) |
| Quad (4×16GB) | 64GB | 4× DDR4-2666 16GB | Quad-channel, maximum capacity |
Best RAM Modules for EliteDesk 800 G5
Kingston Fury Beast DDR4-2666 8GB — Native G5 speed, excellent stability, budget-friendly.
Kingston Fury Beast DDR4-2666 16GB — For reaching 64GB capacity with just four modules.
Corsair Vengeance LPX DDR4-3000 16GB — Slightly faster than native, still compatible and forward-compatible.
G.Skill Trident Z DDR4-2666 16GB — High performance, native speed match, professional grade.
Storage & SSD Compatibility
M.2 NVMe Drives
The EliteDesk 800 G5 supports PCIe 3.0 NVMe M.2 SSDs, providing read speeds of 3,500+ MB/s — a major step up from SATA drives (550 MB/s). Most G5 configurations include one or two M.2 slots depending on the motherboard variant.
Samsung 970 EVO Plus 1TB — Excellent performance, widely trusted, ideal for G5.
WD Blue SN570 1TB — Reliable, cost-effective, proven in enterprises.
Crucial P5 1TB — Balanced speed and cost, solid warranty.
SATA Storage Options
Some G5 configurations retain 2.5″ SATA SSD or 3.5″ HDD bays for secondary storage. SATA SSDs are slower (550 MB/s) but offer affordable high-capacity options for data archival.
Dual Storage Configurations
The G5 can support both NVMe and SATA drives simultaneously — use NVMe for the Windows OS and applications (fast boot), and SATA for bulk file storage or backup drives.
Power Supply Details
Tower PSU Specifications
EliteDesk 800 G5 tower models typically ship with:
- 240W PSU — Standard configuration for i3/i5 processors
- 320W PSU — Higher-power option for i7 configurations
Both are standard ATX 24-pin designs and can be replaced with any desktop power supply rated for the same or higher wattage. Most modern 550W+ ATX PSUs will fit and offer better efficiency.
SFF PSU (Small Form Factor)
SFF EliteDesk 800 G5 models use proprietary or non-standard power supplies. Do not mix SFF and tower PSUs — they use different connectors and form factors.
Recommended Replacement PSUs (Tower)
Seasonic Focus GX-550W 80+ Gold — Excellent efficiency, modular, 12-year warranty.
EVGA SuperNOVA G5 650W — Reliable, quiet, 80+ Gold certified.
Step-by-Step RAM Installation
- Power off the system completely and unplug the power cable
- Wait 30 seconds to allow residual charge to discharge
- Press the power button once to fully discharge static electricity
- Open the case side panel (usually two screws)
- Locate the four DIMM slots (typically along the top edge of the motherboard)
- Push the retention clips at both ends of each slot outward to release existing modules (if upgrading)
- Align the new module with the slot (notch matches the key position)
- Press down firmly on both ends until the clips snap into place
- Replace the side panel and reconnect the power cable
- Power on — the BIOS will auto-detect the new RAM capacity on first boot
Frequently Asked Questions
Q: Is the EliteDesk 800 G5 better than the G4 for RAM upgrades?
A: Yes, in two ways. The G5 supports DDR4-2666 (vs. G4’s DDR4-2400) for slightly faster memory, and the G5 supports up to 64GB (vs. G4’s 64GB limit as well). The practical difference is minimal, but the G5 offers better forward compatibility if you plan to move RAM to newer systems.
Q: My G5 currently has 16GB of DDR4-2400 RAM. Can I add DDR4-2666?
A: Technically yes, but it’s not optimal. Mixing speeds will cause all modules to run at the lowest speed (2400 MHz). For best performance, upgrade all modules to matching DDR4-2666 sets of four.
Q: Does upgrading to 64GB RAM actually improve performance?
A: For typical office work (email, browsing, Word documents), 16-32GB is sufficient. You’ll benefit from 64GB if you run virtual machines, large databases, video editing, or CAD work. For standard business use, 32GB offers excellent headroom at lower cost.
Q: Can I upgrade the storage without replacing the entire drive?
A: Absolutely. If your G5 has an M.2 NVMe slot and a SATA slot, you can keep both drives running simultaneously. Install the NVMe drive for the OS and add a SATA SSD for storage, or vice versa.
Q: What’s the warranty status of my EliteDesk 800 G5 if I upgrade components?
A: Installing RAM or SSDs yourself does not void your warranty. HP explicitly allows user-serviceable upgrades. However, if you damage the motherboard during installation, that specific damage may not be covered. Always ground yourself before handling components.
Q: How do I check how much RAM my G5 is currently using?
A: In Windows, right-click “This PC” or “My Computer” and select “Properties.” You’ll see total installed RAM. For more detail, open Task Manager (Ctrl+Shift+Esc), go to the Performance tab, and check Memory details.
Recommended Products
| Product | Type | Capacity | Link |
|---|---|---|---|
| Kingston Fury Beast DDR4-2666 | RAM | 8GB or 16GB | Shop |
| Corsair Vengeance LPX DDR4-3000 | RAM | 16GB | Shop |
| G.Skill Trident Z DDR4-2666 | RAM | 16GB | Shop |
| Samsung 970 EVO Plus | NVMe SSD | 1TB | Shop |
| WD Blue SN570 | NVMe SSD | 1TB | Shop |
| Crucial P5 | NVMe SSD | 1TB | Shop |
| Seasonic Focus GX-550W | PSU | 550W | Shop |
| EVGA SuperNOVA G5 650W | PSU | 650W | Shop |
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