In January 2023, the US hardware manufacturer NZXT introduced the H9 case series with the Flow and Elite models. Even back then, they offered one thing above all: plenty of space for premium hardware and powerful cooling solutions with the best possible view through two glass walls. Almost two and a half years later, a polished product update now follows, which we would like to present to you in this H9 Flow RGB+ test with one of the three new “H9 Flow RGB+” variants.
According to NZXT, the new Flow 2025, like its predecessor, is a large two-chamber airflow case in mid-tower ATX format that packs high-performance cooling into an impressive aesthetic. The main differences to the predecessor H9 Flow from 2023 are, on the one hand, more space for even larger fans or radiators, namely 420 instead of 360mm for the latter and 140 instead of 120mm for the former. The now slanted front was taken from the H6 Flow and is intended to optimize the airflow once again.
Note on the variant: For this NZXT H9 FLOW RGB+ test, the case was initially made available to us in the “RGB” variant and the missing components (fan and controller) were added later. This is why it can occasionally be recognized as the “RGB” variant in the pictures, such as the product box. Only the 120mm fan at the rear is still part of the “RGB” case variant and would normally come with RGB lighting(F120 RGB Core) in the Plus variant.
Packaging and scope of delivery
- Screws in the scope of delivery are precisely counted
- Three very practical Velcro straps are included on top
The scope of delivery of the H9 Flow RGB+ is manageable. In addition to the case with its two pre-installed 420mm F420 RGB Core fans and the rear F120 RGB Core, it also comes with a control hub for fan and RGB control and accessories for mounting and cable management.
Depending on the setup, the number of screws included in the scope of delivery is counted down to the exact screw and, in this price range, could have done with a bit more just in case. In terms of cable management, the three reusable cable ties with Velcro fasteners were particularly helpful in the H9 Flow RGB+ test.
The complete scope of delivery:
- H9 Flow 2025 case
- 2x F420 RGB Core case fan
- 1x F120 RGB Core case fan
- 1x RGB+Fan Control Hub
- 1x small cable cover
- 3x velcro tape
- 15x cable ties
- 4x power supply screws (6-32 x6mm)
- 17x hard disk screws (6-32 x5mm)
- 24x SSD screws (M3 x5mm)
- 36x fan screws (CB5 x10mm)
- 1x spacer bolt (6-32 x8.5+4mm)
- 1x spacer bolt wrench
Technical features
| DIMENSIONS | |
| With feet | 506 mm 315 mm 481 m m |
| Capacity | 76,7 L |
| weight | 13.4 kg |
| GENERAL | |
| Case type | Midi tower |
| Mainboard compatibility | E-ATX (up to 277 mm), ATX, Micro-ATX, Mini-ITX |
| Support for mainboards with rear connectors (BTF, Project Zero) | Yes (ATX, Micro-ATX) |
| Case materials | SGCC steel, clear tempered glass (white), tinted tempered glass (black) |
| CLEARANCE | |
| CPU cooler height | 165 mm |
| GPU length | Up to 459 mm (with under 56 mm thick fans installed on the front right) Up to 410 mm (with 56 mm thick 420 mm AIO and fans installed on the front right) |
| PSU length | 200 mm |
| Thickness of the top radiator and fan | Up to 80 mm (360 mm) Up to 62 mm (420 mm) |
| FRONT CONNECTORS | |
| USB 3.2 type A | 2 |
| USB 3.2 Gen2x2 Type C | 1 |
| Headphone socket | 1 |
| EXPANSION SLOTS | |
| standard | 7 |
| Vertical | 0 |
| DRIVE BAYS | |
| 2.5 inch | 4+2 |
| 3.5 inch | 2 |
| FAN SUPPORT | |
| Front right | 3 x 120 mm / 3 x 140 m m (1 x F420 RGB Core included) |
| Top side | 3 x 120 mm / 3 x 140 m m |
| Bottom side | 3 x 120 mm / 3 x 140 m m (1 x F420 RGB Core included) |
| Rear side | 1 x 120 mm (1 x F120 RGB (housing version) included) |
| FAN SUPPORT | |
| Front right | Up to 420 mm |
| Top side | Up to 420 mm |
| Bottom side | Up to 360 mm |
| Rear side | Up to 120 mm |
| FAN SPECIFICATIONS | |
| Model | F420 RGB Core, F120 RGB Core (case version) |
| Fan speed | 2000 ± 200 rpm in, 1300 ± 130 rpm |
| Air flow rate | 167.5 m ³/h, 93.7 m ³/h |
| Noise level | 34.5 dB(A), 26.1 dB(A) |
| Fan connection | 8-pin, 3-pin |
| CONTROL HUB SPECIFICATIONS | |
| Fan channels | 3 x NZXT 8-pin (PWM only) / 1 x NZXT 8-pin (DC and PWM control) / 1 x 4-pin PWM (DC and PWM control) |
| RGB channels | 4 x NZXT 8-pin / 1 x NZXT RGB |
| Maximum LED support | Each NZXT 8-pin channel supports a maximum of 96 LEDs. The NZXT RGB channel supports up to 40 LEDs and up to 5 NZXT devices. |
| System requirements | Internal USB 2.0 header 8-pin PCIe power connector |
| WARRANTY | 2 years |
| Manufacturer page |
www.nzxt.com |
| price |
€ 299.90 * |
Design of the NZXT H9 FLOW RGB+
- Lots of space in the main chamber and practical aids in the rear chamber
- The case’s only dust filter is located in the base
As described at the beginning, the H9 Flow RGB+ is a dual-chamber airflow case. The aim here is to move as many cable connections and components as possible from the main chamber to the rear chamber, which faces away from the view. The H9 FLOW RGB+ is also compatible with mainboards with rear connections from various manufacturers (e.g. ASUS BTF, MSI Project Zero), which means even less cable clutter to disturb the eye. The two glass walls on the left and front, as well as the straightforward design with its clear lines and smooth surfaces, also make it the ideal showcase case. The main disadvantages are the high weight and the very unwieldy size.
Five wall elements can be removed from the base frame of the H9 Flow RGB+, the two glass walls and three metal walls. To make things quicker, the most important access points at the top and the two large side panels are each fastened with just two or one knurled screw, which can be loosened by hand. The front glass wall, on the other hand, is attached to the top with 4 screws and can be removed if necessary, for example to make way for space-consuming assembly work.
The two large side panels can be opened individually without having to remove the top panel first. After shipping, the fixing screw of the angled panel at the front right can be removed completely. The only dust filter on the housing is located on the underside, which can be easily pulled out to the left and snaps into place magnetically.
The design of the two chambers
The H9 Flow RGB+ can be adapted to your own requirements in several places. In the main chamber, an extra-wide channel provides access to the most important mainboard connections. It can be reduced in size with two panels or closed off completely if, for example, a motherboard with rear connections is used.
If you want to install a 420 mm radiator behind the front mesh panel, a plastic cover can be removed to create the necessary space. For easier installation of fans and radiators, a mounting frame can also be found here, which can be loosened with just two screws and completely removed along with the first one.
Space is relatively scarce in the rear chamber. NZXT has taken precautions to ensure that occasional mounting does not degenerate into frustration. First of all, the screwed-on SSD panel can be folded to the side or removed completely. This is essential if you want to carry out work on the cabling behind it. After shipping, the screws can be omitted here, the flap then adheres purely magnetically, which allows even faster access.
The hard disk cage can also be loosened with just one knurled screw and removed completely to make it easier to reach the control hub behind it.
For cable management, there are not only three large Velcro strips on the left and three smaller ones above the mainboard, there are also holders for the 15 supplied cable ties in many places.
Build quality
- All parts are visually flawless
- Front USB ports can only be used with increased force
- Screwed metal panels can rattle, one was a little flexible
None of the parts of the H9 Flow RGB+, including the built-in fans, gave cause for complaint in terms of the purely external build quality; all were very cleanly finished. Functionally, minor flaws occasionally marred the otherwise flawless picture. For example, the USB sockets on the front panel are much narrower than usual, which meant that more force was always required to connect devices, almost too much.
In addition, the fact that there is almost always metal-to-metal contact between the walls and the housing meant that rattling noises were often heard. The right-hand metal wall in particular was a little loose at one point. Too much play or a lack of damping at these points could therefore lead to unpleasant noises, for example due to vibrations from the fans. However, this never happened, at least during this H9 Flow RGB+ test.
Justified concern always arose at the beginning when removing the left glass panel while the top cover was still in place. Due to the small clearance and only one attachment point on one side, the force required to remove the panel seemed so great that the glass panel could be damaged. According to NZXT, the case is sturdy enough, which I can confirm after testing it several times. If you want to be on the safe side, you can still remove the top cover beforehand.
Installation of the test system in the NZXT H9 FLOW RGB+
- Despite all the simplifications, the assembly of the test system occasionally required nerves of steel
- The size and weight of the case made it difficult to handle during assembly
To assemble the test system for this H9 FLOW RGB+ test, I decided to completely disassemble the case down to the base frame, leaving only the rear 120mm fan installed.
The test system:
- CPU: AMD Ryzen 9 7950X3D
- CPU cooler: Liquid Freezer III 420 A-RGB
- GPU: NVIDIA GeForce RTX 4060 Ti
- MB: MSI MAG X670E TOMAHAWK WIFI (MS-7E12)
- RAM: 2x G.SKILL F5-6000J3040G32G DDR5
- PSU: Enermax Revolution D.F.X. 1050 (fully modular)
- HDD: 2x 3.5 inch Western Digital
- SSD: 2x 2.5 inch Crucial, SanDisk
CPU compact water cooling and case fan
First of all, I screwed the controller hub for the RGB and fan control (see below) onto the platform provided behind the mainboard.
I installed the radiator and fan of the Liquid Freezer III 420 CPU compact water cooling system in the upper fan slot. Radiators with a combined depth of up to 62 mm can be installed here. The Liquid Freezer is even a few millimeters deeper, but this did not cause any problems in this H9 Flow RGB+ test. For the installation, I turned the case upside down and mounted the fans in a push configuration, so that they would push air upwards out of the case. The Liquid Freezer did not fit into the fan slot at the front right, the radiator and fan were simply too thick or wide for this.
This was followed by the 420mm F420 Core case fans, which are attached with just 4 screws and therefore reduce the installation effort enormously. The removable mounting frame at the front right makes installation even easier if required. I installed the fans in both the bottom and front right slots in the pull configuration, so they draw air into the case from the bottom and front. Incidentally, 140mm fans can be installed in the lower fan slot, but no radiators over 360mm.
Mainboard, power supply and hard disks
There was little to consider when installing the mainboard. The 9 spacer bolts are pre-installed for ATX mainboards, and the instructions show the correct screw connection for other mainboard sizes. It should be noted that power supply units can be a maximum of 200mm long, so the installed Revolution D.F.X. 1050 was completely unproblematic with a length of 140mm.
Very convenient: I was able to install the two 3.5 inch hard disks outside the case in the hard disk cage and then fasten it to the rear panel of the case with a single knurled screw.
Enclosure connections and SSD drives
The cable harness of the H9 Flow RGB+ contains the connections for the front panel and the case fans. Instructions and labeling helped with the correct assignment. The combined F_Panel connector and the ample cable management equipment of the case were particularly helpful for the cabling itself.
The SSDs were just as easy to install in the designated flap as the hard disks were in their cage. The cabling of the housing fans is described under the Control Hub and Cam app.
The finished test system for the NZXT H9 Flow RGB+ test
Once the most important components were installed and the cables routed, the CPU cooler and graphics card were added. A vertical graphics card holder is available separately. Finally, only the glass and metal covers were reattached. All in all, the result was more satisfactory than the way there. The size and, above all, the high weight of the case together with the installed components made it considerably more difficult to handle during assembly.
The accessibility of the rear chamber is increased by certain tricks. However, the layered structure requires a plan from the outset. Otherwise, the frequent installation and removal of the component that is currently interfering in order to access the area behind it becomes a source of frustration.
Unfortunately, the maximum thickness for radiators in the slanted front of the case was also not clear from the available information material. As a result, a lot of time was lost in an unsuccessful installation attempt.
Admittedly, any hardships were quickly forgotten as soon as the case was switched on for the first time and the fans bathed the interior in bright light.
Control hub and cam app
- NZXT’s 8-pin connection cable for the RGB F-Core fans saves time and nerves
- Cam app with slightly increased CPU load in idle mode
The H9 FLOW RGB+ comes with a digital control hub for RGB and fan control, which is connected to a free PCIe connector on the power supply and an internal USB 2.0 header on the mainboard. It is mounted behind the mainboard either magnetically, with 2 screws or the dual lock straps included in the scope of delivery.
Accessories of the Control Hub:
- 1x NZXT 8-pin splitter
- 1x NZXT RGB splitter (1 to 3)
- 1x 4-pin PWM fan splitter (1 to 3)
- 2x 3M Dual Lock straps
The hub is divided into 5 channels. The built-in F420 Core and F120 Core RGB fans are connected directly to channels 1 to 3 with PWM support via an 8-pin connector. NZXT’s own 8-pin connector type, which combines the RGB and PWM cables of the RGB F-Core fans, makes installation much easier. Other devices with NZXT RGB, 3-pin DC or 4-pin PWM connection can be plugged into the other connectors.
NZXT’s Cam app is then required to configure the connected devices. Cam can be customized according to your own preferences, for example, you can hide menu items that are not needed. Not quite so nice: Cam was often the app with the highest CPU load in the process list when idle on the desktop, namely between 0.5 and 1% of the total load.
RGB lighting of the H9 Flow RGB+
- Precise RGB control via cam and control hub with many customization options
- Devices with 3-pin 5V ARGB cannot be connected to the Control Hub without an adapter
To make optimum use of the RGB function of the H9 FLOW RGB+ or its RGB fans, they can be connected to the supplied Control Hub. However, you can also choose your own solution using the corresponding adapter cables, such as the corresponding RGB headers on the mainboard.
The only problem in my test scenario was the incompatibility of the Liquid Freezer III 420’s RGB (3-pin 5V ARGB) with the Control Hub (proprietary 4-pin NZXT RGB). This made it impossible for me to have the hub take over the RGB control of ARCTIC’s AIO, as there was no 5V ARGB to NZXT RGB adapter.
Mainboard and MSI’s Mystic Light stepped in instead. The RGB test therefore took place simultaneously with two control systems, which fortunately could be coordinated well with each other. As the F-Core fans have all the necessary connections via adapters, it would also have been possible to leave the entire RGB control to the mainboard.
The RGB configuration via cam and control hub ultimately worked without any problems. There are various static and animated programs, all of which can be fine-tuned in terms of color and brightness. In some cases, LEDs can also be controlled individually.
Cooling performance test of the H9 Flow RGB+
- Very good cooling performance with low noise level in operation with reduced fan speed
- Ryzen 9 7950X3D and NVIDIA GeForce RTX 4060 Ti reached 49 and 52.5 °C (Delta T)
The H9 Flow RGB+ from NZXT is designed for high airflow and has an ultra-fine grille on the front right side, which is intended to maximize airflow and filter dust at the same time. It also comes with three pre-installed case fans: two RGB Core F420 single-frame fans and the case version of the RGB Core F120 fan at the rear. The rear slot can accommodate a maximum of one 120mm fan. The fans can be controlled via a dedicated solution or the supplied control hub, which in turn can be configured via the Cam app. For this H9 Flow RGB+ test, I had both the case fans and the CPU cooler controlled via Cam.
For the temperature test, I loaded the CPU and GPU with benchmarks for 10 minutes each and recorded the average temperature. I specify the temperature as Delta T, i.e. minus the room temperature. I first let all the fans run at 100% of their maximum speed, then I reduced the speed in Cam to a level that produced a noise level of 36 dB. The installed Ryzen 9 7950X3D was cooled by ARCTIC’s Liquid Freezer III 420, the NVIDIA GeForce RTX 4060 Ti ran with a stock cooler.
- Room temperature: ~22 C°
- Test length/warm-up phase: 10 / 1 min.
- CPU benchmark: Cinebench 2024.1.0 – CPU multicore
- GPU benchmark: Furmark 2 2.8.0.0 – Resolution: QHD, Anti-Aliasing: Off
- System info software: HWiNFO 64 v8.12-5555
- Volume measurement: Android smartphone + Sound Meter app
- Maximum TDP: CPU 143 W / GPU 159 W
Result of the cooling performance test
| Fan setting in Cam | 100% (fixed) | 34% (fixed) |
|---|---|---|
| CPU temperature Ø idle / full load (Delta T) | 18,6 / 48,1 °C | 19,2 / 49 °C |
| GPU temperature Ø idle / full load (Delta T) | 7,1 / 51,6 °C | 9,8 / 52,5 °C |
| Noise level | 67 dB | 36 dB |
| Speed (F420 RGB Core) | 2000 RPM | 760 RPM |
The average temperature reached by the CPU was 49 degrees above room temperature with reduced fan speed and 10 minutes of full load in the Cinebench multicore benchmark. The graphics card reached 52.5 degrees in Furmark under the same conditions. This small cooling performance test shows that the H9 Flow RGB+ cools the installed components excellently even at low and therefore quiet speeds of around 760 rpm. Consequently, this test system has not even come close to reaching its full potential, although this was to be expected. The case makes particular sense in combination with high-end components with high power dissipation, whose heat development needs to be managed quickly and effectively.
Conclusion of the NZXT H9 FLOW RGB+ test
According to NZXT, the H9 FLOW RGB+ is aimed at enthusiasts who are looking for a showcase case for powerful high-end components. The new edition of the H9 Flow from 2023 presented here comes with more than enough space for the largest graphics cards and up to two 420mm radiators. The good cable management was particularly enjoyable when installing the test system. Its size and weight, on the other hand, were a hindrance and the well-designed accessibility was not always noticeable. However, once the system was switched on for the first time, the stresses and strains were forgotten. Then the astonishment at the excellent cooling performance and the brilliant RGB lighting set in.
In terms of quality, this H9 FLOW RGB+ test did not reveal any serious defects in the case or the installed parts. To a lesser extent, the narrow USB sockets, a somewhat wobbly right wall and, due to a lack of damping, generally somewhat rattling metal walls are worth mentioning here. As far as the equipment is concerned, it is also worth asking whether a single dust filter is sufficient for the entire case and whether the screws really had to be counted down to the last detail. Another pity was the lack of an option to connect 5V A-RGB devices directly to the control hub, where proprietary solutions are clearly preferred. In any case, the cooling performance and RGB lighting were absolutely convincing on both sides.
At € 299.90 *, the basic H9 Flow version is priced at the same level as comparable mid-tower cases. These include the Lian Li PC-011 Dynamic and O11 Dynamic EVO or the Hyte Y60 and Y70. However, the H9 Flow surpasses them, particularly in terms of cooling options and space for graphics cards. The high price difference between the cheaper H9 Flow or H9 Flow RGB variant and the RGB+ variant could make the former appear more attractive. However, it can certainly be justified by the F420 and F120 Core RGB case fans, which are easier to install and wire. If you want to use your own fans and your own control solution, you can still save a lot of money with the basic version and won’t make a mistake.
- Very high cooling capacity
- good workmanship
- quick access to the interior
- Space for two 420mm radiators
- Space for large graphics cards
- bulky and very heavy
- only one dust filter
- very proprietary control hub
NZXT H9 FLOW RGB+
Processing
Structure
Equipment
Cooling
Price-performance ratio
95/100
The NZXT H9 FLOW RGB+ is a visually very appealing mid-tower case with enormous cooling potential. It offers space for very large radiators and graphics cards, very good cable management and quick access to the interior. The built-in RGB Core fans are controlled by the in-house Control Hub.
