Expert’s Rating
Pros
- Stable for workplace work and productiveness
- Easily accessible connections
- Fast Wi-Fi
Cons
- Minimal upgradeability
- Some cooling noise
- Older processor
- Somewhat costly for what you get
Our Verdict
The HP Pro Mini 400 G9 might not be the prettiest or strongest mini PC we’ve ever seen, but it surely gives dependable efficiency for searching and day-to-day duties.
Best Prices Today: HP Pro Mini 400 G9
$956.42
HP has a number of variations of mini PCs and the Pro Mini 400 is their most compact but. The newest version known as the G9 and it’s bought in many various configurations, with 12th or 13th technology Intel Core i5 or Core i7 for desktop computer systems and numerous quantities of reminiscence and SSD. There may also be variants with or with out Wi-Fi, which is just a small M.2 card mounted in a regular place within the pc.
My examined mannequin has an Intel Core i5-12500T, which is a extra power environment friendly model of the “regular” i5-12500, 16GB RAM, and 256GB SSD. It’s one of many cheaper variants. It’s additionally obtainable with 8GB of RAM, however I wouldn’t suggest that. A couple of hundred {dollars} for twice as a lot is effectively definitely worth the cash.
Performance is sweet, however not nice. The processor’s six cores are good at pushing particular person cores excessive for brief durations of time, however don’t achieve this effectively for top steady hundreds. This ends in excessive Geekbench outcomes and decrease Cinebench scores in my measurements. It matches the expertise after I use the pc. Editing and chopping a video undertaking is clean and seamless even with numerous results and brief sequences with many layers, but it surely takes longer to export the outcome.
Looking to choose up a brand new laptop computer? Check out PCWorld’s roundup of the best laptops obtainable proper now.
HP Pro Mini 400 G9: Design
The Pro Mini 400 is a flat little field, measuring simply over 17x17cm large/deep, and fewer than 4cm thick. It’s designed to face on a desk or cling on the again of a pc monitor. HP additionally sells mounting kits for it as an adjunct, however doing so is a bit impractical, as all of the connections are deep into the again of the monitor and it’s solely appropriate for chosen HP screens.

Mattias Inghe
On a desk, it’s discreet and stands firmly on rubber ft, although it’s not probably the most enticing factor on the planet. A black, flat aluminum tube with connectors and cooling grids on the flat back and front. Built extra for practicality than ornamentation, you get loads of quick USB ports and headphone jacks available within the entrance panel.
There’s additionally a small speaker, which the pc has as a backup when you don’t have another audio gadget linked through headphones, USB, or display. It doesn’t sound nice, but it surely’s higher than you’d count on and can be utilized in emergencies to listen to what’s being mentioned in video conferences or to play system sounds and movies. But we’d suggest connecting a headset or exterior audio system as an alternative.
You get loads of connections on the back and front of the gadget, and also you gained’t want a USB hub anytime quickly. Mostly USB-A, but in addition a USB-C. One port on the entrance and one on the again has an influence provide to cost your cell phone, for instance.
HP Pro Mini 400 G9: Easy to open
The high may be loosened and eliminated with a screw on the again for upgrades and upkeep. Not that there’s a lot to do when you’re inside. There’s a free SO-DIMM slot for inserting further reminiscence, however that’s it. If you wish to increase the storage, you’ll have to switch your entire SSD with a bigger one. But at the least the SSD is simple to entry in contrast to the reminiscence that’s hidden underneath the system fan.
According to unconfirmed info, it needs to be attainable to put in a 2.5-inch disc within the pc, however there’s no inner SATA port. Is it definitely worth the problem? No, join extra storage on USB as an alternative. It works completely effectively.
HP will get a gold star for an bold try and maintain the fan noise down regardless of a strong desktop processor. It has some lively cooling always, but it surely’s nearly not possible to listen to it when it’s switched on however passive. And full load of the processor doesn’t pull up the RPMs a lot that they’re distracting.

Mattias Inghe
HP Pro Mini 400 G9: Cooling
One cause for its restricted efficiency in sure conditions could also be that HP has chosen subdued cooling over steady most load. On the opposite hand, the pc usually will get a transparent buzzing tone at medium load that may be a bit annoying, however I’ve heard worse.
You can nonetheless purchase the HP Pro Mini 400 G9 with Windows 10 Pro, which Microsoft nonetheless permits for enterprise computer systems. Then you get a free improve to Windows 11 Pro if you need it. However, you possibly can’t return to Windows 10 Pro once more when you change your thoughts.
My take a look at pattern had already made the change to Windows 11, so I couldn’t go on a nostalgia journey. I like to recommend that particular person customers stick to Windows 11 for future compatibility and updates. Microsoft is phasing out help in 2025. You gained’t have any bloatware apart from some pointless issues that all the time include Windows. The solely issues HP provides are occasional apps that management particular {hardware} in addition to help options and a digital guide.
HP Pro Mini 400 G9: Rating: 3 out of 5
HP Pro Mini 400 G9: Specifications
Product Name: HP Pro Mini 400 G9
Tested: January 2024
Manufacturer: HP
Tested mannequin: 6B2D9EA#UUW
Processor: Intel Core i5-12500T, 6pcs P-core 2-4.4 GHz
Graphics: Intel UHD Graphics 770
Memory: 16GB DDR4
Storage: 256GB
Expansion slots: 1 SO-DIMM
Connections: USB-C 20 Gbit/s, 2pcs USB-A 10 Gbit/s, headset entrance. USB-A 3 10 Gbit/s, 2pcs USB 2.0 5 Gbit/s, lan, 2pcs DisplayPort, HDMI rear.
Wireless: Wi-Fi 6e, Bluetooth 5.2
Operating system: Windows 11 Pro (pre-installed with Windows 10 Pro downgrade)
Other: Speakers
Noise degree: 27-35 dBa
Size: 17,7 x 17,5 x 3,42 cm
HP Pro Mini 400 G9: Performance
Cinebench R23, cpu all cores: 7,834 factors
CinebenchR23, cpu single core: 1,396 factors
Geekbench 6, cpu all cores: 7,122 factors
Geekbench 6, cpu single core: 2,286 factors
Geekbench 6, graphics: 7,001 factors
Disk learn: 3,163.23 MB/s
Disk write: 1,920.2 MB/s