Fractal’s Define S is rather plain looking but its minimalism has a certain elegance. Plastic is used on the front and roof but, on the front at least, it has an attractive faux brushed-metal finish. Steel is used everywhere else, with overall high build quality and thick rubber feet.
The front panel is solid, aside from the side ventilation sections, and there’s no need for a door, since there’s no fan controller nor optical drive mounts to access. The panel does pull off, though, revealing a full-height dust filter for the intake area where a 140mm fan is fitted. A second 140mm fan is mounted as a rear exhaust, but there’s space for an impressive eight in total.
The PSU and bottom fan mount are covered by a slide-out dust filter, although it can be tricky to get back into place – the case could do with a little more clearance here. The top three fan mounts, meanwhile, are protected by individual blanking plates, although they’re a little fussy to remove, requiring you to unclip them from inside. You don’t get dust filters for this area, however, so you should only remove these plates if you’re installing fans or a radiator in exhaust mode here.
The side panels are held in place with captive thumbscrews, which are a neat touch, but the notches and rails system are less appreciated. There’s also noise-dampening on the right side panel, but you don’t get any on the large windowed panel. On the plus side, the PSU is properly isolated from the case, although there’s no PSU cover as seen in the Phanteks or NZXT cases.
What makes the S model notably different from Fractal’s similar R5 is the lack of 5.25in or 3.5in drive cages, meaning that the main working area is extremely spacious with massive amounts of clearance. It gives airflow a very clear path, and also nets the Define S outstanding water-cooling support for a £70 mid-tower. You can fit 280mm and 360mm radiators in the front, while the roof supports 360mm and even 420mm models. Roof radiators based on 140mm fans are limited to slim models only, but thicker setups can be installed when you use ones with 120mm fans, thanks to offset mounting holes. You can also use two 360mm radiators together without conflict. Furthermore, at the front of the elongated motherboard tray is a set of reservoir mounting points, as well as a pump mounting area built into the floor.
All drives are installed behind the motherboard tray on individual metal trays released via a single thumbscrew. You do need screws for all drive types, but it’s a quick process and 3.5in drives have anti-vibration mounting points too. The Define S could do with a more space for cable management, but the routing holes are large and covered by rubber grommets. All internal cables are black for consistency too, and the Velcro cable ties are a real bonus, making tidying much easier than usual.
The open interior results in very good airflow as well. The large 140mm at the back pushes the Fractal to the top of the CPU cooling charts in this test, with a delta T of 52°C (Core i7-870). The same delta T for the GPU (HD 5870) is also a strong result. There’s no fan control, but the Define S is still pretty quiet, even with the two fans at full speed.
The Define S cools well out of the box without much noise, and offers plenty of room for expansion and water-cooling gear. A fan controller and PSU cover would be welcome, but most key features are covered. It’s one of the easiest cases to work with too, and the price is fair.