HP Pro Mini 400 G9 — Quick Specs Summary
| Component | Specification | Upgradeable? |
|---|---|---|
| Processor | Intel Core i5/i7 13th-gen (5–8 cores, 3–5.4 GHz) | No |
| RAM | 8GB, 16GB DDR4 SO-DIMM (2 slots, max 64GB) | Yes — UPGRADEABLE |
| Internal SSD | 256GB–512GB M.2 NVMe | Yes — replaceable |
| Ports | 4× USB-A 3.2, 1× USB-C, HDMI 2.0, Gigabit Ethernet | Expandable via dock |
| Wireless | WiFi 6, Bluetooth 5.2 | No |
| Power Supply | 65W USB-C PD | No |
| Price | £350–450 | N/A |
Pro Mini 400 G9: Latest Intel Professional Mini PC
Performance & Positioning
Intel 13th-gen (i5/i7) with professional-grade support. No vPro (unlike EliteDesk), but solid for SMB deployments. Performance excellent for development, office work.
DDR4 + Single M.2
Budget-friendly DDR4 SO-DIMM. Single M.2 slot (no 2.5″ SATA option). Clean, simple upgrade path.
RAM & SSD Upgrades
DDR4 Path
- Factory: 8GB or 16GB DDR4
- Upgrade to 32GB: £50–80
- Upgrade to 64GB: £100–150
M.2 NVMe
Single slot (256–512GB factory). Replace existing or upgrade capacity. Cost: £30–60 for 512GB upgrade.
Installation
- Power down, unplug
- Remove bottom panel
- RAM: Push tabs, eject at 45°; insert new DDR4
- M.2: Push at 30°, eject; insert new NVMe
- Reassemble, boot
Compatible RAM: Crucial DDR4-3200 16GB SODIMM, Kingston ValueRAM DDR4-3200. Compatible SSD: Samsung 990 EVO, WD Blue SN580, Crucial P3 Plus.
Power & Cooling
65W USB-C PD; quiet operation. Adequate for i5/i7-13th gen sustained workloads.
Connectivity
4× USB-A + USB-C + HDMI 2.0. Good for office peripherals; no Thunderbolt or dual storage.
Upgradeability Score
| Category | Score |
|---|---|
| RAM Upgrade | 9/10 |
| SSD Upgrade | 8/10 |
| Ports & Connectivity | 7/10 |
| Display Support | 5/10 |
| Overall Upgradeability | 7/10 |
Frequently Asked Questions
Pro Mini 400 G9 vs ProDesk 400 G9?
Very similar (both Intel 12/13th-gen, DDR4). Pro Mini slightly different branding/features. Choose based on price and availability.
Can I upgrade to 64GB?
Yes. 2× 32GB DDR4 SO-DIMM (£100–150).
Should I buy this?
Yes, good value for SMB. Latest Intel 13th-gen, clean upgrade path. No vPro (not needed for most users).
How long supported?
Intel 13th-gen through 2027–2028. Excellent long-term support.
Better than Geekom alternatives?
Pro Mini: Professional support, warranty. Geekom: More features (USB4, dual SSD), same performance. Choose based on support needs.
Recommended Products
These are the products we recommend based on this guide. All links go to Amazon UK where you can check current prices and availability.
| Product | Why We Recommend It | Amazon UK |
|---|---|---|
| Corsair Vengeance DDR4 SO-DIMM 32GB (2×16GB) 3200MHz | Best overall DDR4 upgrade kit | View on Amazon UK |
| Kingston Fury Impact DDR4 SO-DIMM 32GB (2×16GB) 3200MHz | Reliable alternative with tight latency | View on Amazon UK |
| Crucial DDR4 SO-DIMM 16GB 3200MHz | Budget single-stick upgrade | View on Amazon UK |
| Samsung DDR4 SO-DIMM 32GB 3200MHz | OEM-quality for business laptops | View on Amazon UK |
| Samsung 990 Pro 2TB NVMe M.2 2280 | Fastest consumer NVMe — ideal for gaming & editing | View on Amazon UK |
| WD Black SN850X 2TB NVMe | Excellent Gen4 speed with heatsink option | View on Amazon UK |
| Crucial P5 Plus 1TB NVMe | Great value Gen4 SSD | View on Amazon UK |
| Kingston NV2 1TB NVMe | Budget-friendly with solid reliability | View on Amazon UK |
Prices and availability may vary. As an Amazon Associate, we earn from qualifying purchases.
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Prices from PCHub.UK via ComputersDeal. As an affiliate, we may earn from qualifying purchases. Prices updated 2026-04-10 13:15:58.
