NZXT H3 Flow (2025) White Micro-ATX Airflow Mid-Tower PC Case with Tempered Glass, USB-C Gen 2x2 Front I/O, 280mm Front Radiator Support, Rear-Connect Ready (mATX) — CC-H31FW-01

The NZXT H3 Flow (2025) in White is built for people who want a clean-looking PC that also takes airflow seriously. It targets that sweet spot where a case is compact enough to feel modern and space-efficient, but still practical for real gaming and creator hardware—full-size GPUs, tall air coolers, and liquid cooling where it makes sense. The “Flow” identity is important here: this model is made to help your components breathe, which is the foundation of sustained performance and lower fan noise during long sessions. Instead of forcing you into a compromise between looks and cooling, the H3 Flow is shaped around the idea that a great-looking build should also run comfortably under load.

At its core, the H3 Flow (2025) is a Micro-ATX case that also supports Mini-ITX motherboards. That gives you a wide range of build options: a compact everyday workstation, a high-FPS gaming rig, or a small creator PC with strong cooling headroom. It’s especially attractive if you’re building around the Micro-ATX format for value and expansion flexibility, while still wanting a case footprint that doesn’t dominate your desk or room. NZXT also lists support for rear/back-connect motherboard designs—an increasingly popular feature for ultra-clean cable management—though that rear/back-connect support is limited to Micro-ATX boards. If you’re aiming for a minimalist “no-cable” look through the glass side panel, this is one of the more practical enclosures to start from.

The White version combines a steel chassis with an ultra-clear tempered glass side panel. That choice of materials matters for both aesthetics and usability. Steel provides a rigid structure that helps with long-term durability, and tempered glass gives you the clean “showcase” side view people expect for modern builds—especially if you’re running RGB memory, a clean GPU, or a tidy cable layout. The ultra-clear glass helps preserve the true color of your components and lighting, so whites look white and colors don’t feel muted. The result is a case that can fit a minimal all-white theme or a mixed black-and-white build while still keeping a sharp, premium look.

Despite the compact design, hardware clearance is one of the H3 Flow’s biggest strengths. It supports CPU coolers up to 170 mm, which is enough for many performance-focused tower air coolers. That means you’re not forced into a small low-profile cooler just because you want a smaller case. On the GPU side, the case supports up to 377 mm graphics cards when there are no front fans installed. Realistically, most builds will include front fans—and NZXT provides more precise configuration-dependent GPU clearance to keep expectations honest. With front fans installed, GPU clearance is up to 352 mm. If you go further and install a front radiator with fans, clearance is up to 317 mm. That range is important because it lets you plan properly: you can prioritize maximum GPU length, prioritize front radiator cooling, or balance both depending on your parts list. It’s a straightforward, transparent approach to compatibility that reduces surprises during assembly.

Cooling flexibility is where the “Flow” direction becomes practical. The case supports a front radiator up to 280 mm and a top radiator up to 240 mm, allowing you to plan a cooling strategy that matches your CPU and overall build goals. If you prefer air cooling, the fan mount layout gives you the ability to build a strong front-to-back airflow path and keep temperatures stable across CPU, GPU, and VRM zones. Fan support includes front mounting for two 120 mm fans or two 140 mm fans, top mounting for two 120 mm or two 140 mm fans, bottom mounting for two 120 mm fans, and a rear 120 mm fan position. NZXT includes one rear 120 mm fan (F120Q Airflow) out of the box, so you immediately have exhaust capability without needing to buy extra fans on day one. That included rear exhaust is especially useful for first boot, cable testing, and baseline airflow while you decide if you want to add front intake fans or liquid cooling later.

The top-and-front radiator support also makes it easier to tune for silence or performance. A front-mounted radiator can help control CPU temperatures under sustained multi-core loads, while top placement can be useful depending on your layout and priorities. Meanwhile, front 140 mm fans (if you choose them) can move a lot of air at lower RPM, which can reduce overall noise while maintaining strong airflow. In a smaller case, good airflow paths matter even more because heat density is higher. The H3 Flow addresses that with a mounting layout that encourages straightforward airflow: intake from the front and/or bottom, exhaust through the rear and/or top.

Connectivity is modern and simple. The front I/O includes one USB 3.2 Type-A port and one USB 3.2 Gen 2x2 Type-C port. That Type-C Gen 2x2 support is valuable if you routinely move large files to fast external SSDs or if you prefer USB-C peripherals. It’s a practical feature for both creators and gamers, because it reduces reliance on rear I/O and makes the case feel current for years. One important detail: the case does not include a 3.5 mm headset jack on the front I/O. If you rely on front audio, you’ll want to plan on using your motherboard’s rear audio, a monitor audio pass-through, or a USB headset/DAC.

Internally, storage support is designed for modern builds that lean heavily on NVMe SSDs but still want a place for SATA drives. The drive bay layout supports 2.5-inch drives (listed as 1+2) and one 3.5-inch drive. That’s a sensible arrangement for a compact Micro-ATX case: you can run a dedicated 3.5-inch HDD for mass storage plus multiple 2.5-inch SSDs if needed, while most users will keep their main OS and game library on M.2 SSDs installed directly on the motherboard. Power supply clearance is listed up to 185 mm, giving you flexibility for many mainstream PSUs while keeping cable routing manageable.

Cable management is easier when a case gives you space to work, and the H3 Flow lists up to 31.5 mm of cable routing space. That’s meaningful in a compact chassis because it increases your odds of a clean side panel fit and reduces the struggle of closing the case after installing thicker cables. A tidy cable layout isn’t just cosmetic—clean routing also helps airflow by reducing obstructions, which matches the “Flow” idea of keeping air moving smoothly through the case.

From a build and compatibility standpoint, expansion is also straightforward: the H3 Flow includes four standard expansion slots. There is no vertical GPU kit support and zero vertical slots listed, which keeps the design simple and avoids clearance conflicts that can appear in smaller cases. This case is focused on reliable, traditional GPU mounting and predictable airflow behavior.

To sum it up: the NZXT H3 Flow (2025) White is a compact Micro-ATX chassis that aims to deliver what most modern builders actually need—strong cooling support, honest compatibility specs, modern front I/O with fast USB-C, and a premium tempered-glass presentation—without inflating size unnecessarily. It’s a strong choice if you want a clean-looking airflow case that can handle serious parts, and it’s especially appealing for tidy builds where cooling and aesthetics need to coexist without compromise.