Fractal Design’s Define R5 is my favorite case in TR’s labs right now. It’s quiet, it cools well, and it’s a breeze to work in. It’s also one of the rare cases we’ve deemed worthy of our Editor’s Choice award. At $110 and up, however, it’s positioned toward the high end of the mid-tower case market, and some buyers might not need all of the bells and whistles, or storage space, that the R5 offers.
Fractal Design appears to agree with this view. The Define S, the latest addition to the Define series, is a somewhat stripped-down—and more affordable—version of the R5. Fractal has taken a scalpel to some of that case’s extras to get the price down, but it’s kept a lot of what made the R5 so good—and it’s given the Define S a couple of new tricks inside.
Looking at the Define R5 and Define S side-by-side, one could be forgiven for having a hard time telling the two apart. The visual differences are subtle. The S’s front panel is a stealthy black plastic with a simulated brushed-metal finish. It feels decent, if a bit cheaper than the R5’s foam-lined door. The window on the Define S extends for the whole length of the side panel, all the better for showing off the system inside. Fractal removed the noise-dampening foam from this panel, likely due to the increased window area, but the right side panel is still dampened.
Behind the front panel, there’s a full-height magnetic dust filter for the three adjustable 120-mm or 140-mm fan mounts. Radiators as large as 360 mm can be mounted here, as well. Fractal has expunged all traces of 5.25″ bays from the Define S, and I’m 100% OK with that. Buyers who still need an optical drive will have to resort to an external unit, though.
Up top, Fractal carries over its excellent ModuVent system. These three foam-backed plastic panels can pop off as needed to reveal mounts for radiators or fans. When left in place, they serve to dampen system noise. Three 120-mm or 140-mm fans can be installed underneath the top panel with the ModuVents removed, as well as a radiator up to 420 mm long.
The I/O cluster features a big, round power button flanked by a reset button, headphone and mic jacks, and a pair of USB 3.0 ports.
Moving around back, the subtle differences continue. The Define S’s rear wall isn’t perforated at all save for the fan grille, and it loses the R5’s adjustable rear fan mount. That’s a bit of a shame. One of the little delights of the Define R5 came when I was able to reposition its rear fan to avoid interference from a top-mounted radiator.
The bottom of the case holds a dust filter for the power supply and the bottom fan mount. This filter pulls out from behind the case, which is rather inconvenient. The Define R5’s filter pulls out from the front, and it’s much easier to work with. Four thick rubber feet isolate the case from floors or desktops.
Here’s a table of specs for the Define S, for easy cross-referencing with our other case reviews:
|Fractal Design Define S|
|Dimensions (W x H x D)||9.2″ x 17.8″ x 20.5″ (233 x 451 x 520 mm)|
|Supported motherboards||Mini-ITX, microATX, ATX|
|3.5″ drive mounts||3|
|2.5″ drive mounts||5 (3 2.5″ or 3.5″ combo sleds, 2 dedicated)|
|Fan mounts||8 (windowed), 9 (non-windowed)|
|Included Fans||1x Fractal Design Dynamic GP14 140-mm front intake
1x Fractal Design Dynamic GP14 140-mm rear exhaust
|Front panel I/O||2x USB 3.0
|Max. graphics card length||16.7″ (425 mm)|
|Max. CPU cooler height||7″ (180 mm)|
|Gap behind motherboard||0.8″-1.6″ (20.3 mm-40.6 mm)|
The Define S is down five 3.5″ drive mounts versus the R5, though the S’s three 3.5″ and two 2.5″ mounting sleds should be more than enough storage room for the average system builder these days. Those who need more storage will have to step up to the Define R5 or look elsewhere, though. The Define S also loses the R5’s three-header manual fan controller, but that’s another perk I doubt most will miss.
The net result of Fractal’s scalpel-wielding is a lower price point. The windowed Define S that I’m looking at today will run you $85 on Newegg right now, down from the $90 list price, while the non-windowed version is $10 less.
When the R5 and the S are both selling at full price, there’s a $30-$40 gulf between them, but since the R5 is also on discount right now, the difference is closer to $15-$25. That small of a step up muddies the Define S’s value proposition, though discounts do come and go. If you’re stuck between the two cases, it might be worth keeping an eye on the prices.
Now, let’s pull off those side panels and take a look at Fractal’s vision for the future of PC cases.
Look, ma, no drive cages
The Define S is strikingly different inside compared to any other ATX mid-tower I’ve used. The main chamber is completely open from front to back, with no provisions for storage devices of any kind. Cutting out the drive cages seems mostly like a cost-cutting measure, but Fractal uses the space freed up this way to make some interesting provisions for custom liquid-cooling setups.
The sheet metal in front of the motherboard tray, where drive cages would typically go, is instead perforated with groups of pegboard-like holes. These holes can be used to mount a liquid-cooling pump or reservoir using a set of included brackets. The open design could benefit air-cooled builds, too: airflow from the front fan mounts has an unobstructed path to the rest of the system. Out of the box, a single Fractal Design Dynamic GP14 140-mm fan blows air into the case, and another at the rear handles exhaust duties.
The motherboard tray of the Define S is inset like its fancier sibling’s, though it’s not as complicated a stamping. I really like this design, since it makes room for taller tower-style air coolers without making the case itself wider. A ring of large rubber grommets surrounds the tray for clean cable routing.
Here’s the Define S’s party trick: Fractal puts three 2.5″ or 3.5″ combo sleds behind the pegboard area, plus another pair of 2.5″ sleds behind the motherboard tray. This design makes perfect sense, but I’m curious to see what effect it has on drive temperatures, since there’s no direct airflow to any of the storage mounts—just some vent holes in the front panel of the case.
This is also all the room you get for storage. There’s no way to add drive cages to the main chamber without some custom work. Be careful about adding too many 3.5″ hard drives into your cart if you’re building a system around the Define S.
Fractal includes its trademark hook-and-loop cable straps behind the motherboard, but room for cable routing here is rather sparse compared to the Define R5’s generous 1.5″ all-around. In the 3.5″ drive area, there’s about 1.6″ (40 mm) of cable space, but directly behind the motherboard, clearances fall to about 0.8″ (20 mm). Most cables should be able to run through the roomier drive area, so the tight clearances might not be a problem in practice. We’ll see in a moment.
Popping out the ModuVents up top reveals a series of offset fan and radiator mounts. The offset design leaves two inches (50 mm) between the motherboard tray and a 140-mm radiator, while 120-mm heat exchangers clear the tray by 2.8″ (70 mm). Fractal cautions that 140-mm-based radiator stacks shouldn’t exceed 2.2″ (55 mm) in thickness here, though 120-mm-based setups aren’t subject to that limitation.
On the floor of the case, there are the usual rubber mounting feet for PSUs along with another 120-mm or 140-mm fan mount. Up front are mounting points for a liquid-cooling pump. Fractal says a wide range of Laing DDC and D5-type pumps can be mounted here, but be sure to check the mount’s dimensional drawing in the manual before buying any parts.
Putting it all together
Building a system in the Define S is remarkably easy. The only way it could have gone better is if the case had put the PC together for me. Get on that, Fractal.
Without a liquid-cooling loop in the Define S, a lot of space in the main chamber goes unused. That certainly makes for a more open airflow path, but this case really cries out for a custom loop. The pegboard area and pre-drilled pump mounting holes are expressly designed to make the installation of that equipment easier.
Unfortunately, I don’t have a custom loop on my parts shelf, but I am going to test out the next-best thing. Cooler Master’s Nepton 240M fits nicely on the Define S’s top panel, and I’ve set it up as an exhaust here. After popping out a pair of ModuVents, installing the 240M was a snap. (This picture is from the Define R5, but the two cases use identical top panels.)
Storage mounting and cable routing are both effortless in this case, aside from one minor point: the inset motherboard tray doesn’t work with right-angle SATA cables, so make sure to have some regular ones on hand. The built-in hook-and-loop straps work great, and I had no problems getting the right side panel back on, even with a full complement of power and data cables running behind the motherboard.
With the Casewarmer system in place, let’s move on to cooling and noise performance testing.
Our testing methods
Here are the specifications of my test system:
|Motherboard||Asus Crossblade Ranger|
|Memory||8GB AMD Entertainment Edition DDR3-1600|
|Graphics card||Zotac Nvidia GeForce GTX 660 Ti AMP! Edition|
|Storage||Kingston HyperX 120GB SSD
Samsung Spinpoint F1 750GB HDD
|Power supply||Cooler Master V550|
|CPU cooler||Cooler Master Hyper D92 (air)
Cooler Master Nepton 240M (liquid)
|OS||Windows 8.1 Pro|
Thanks to Fractal Design for the Define S, and to Asus, AMD, Kingston, Zotac, and Cooler Master for their hardware contributions, as well.
The Define S’s opponent in today’s tests is Corsair’s Obsidian 450D. I’ll be using identical coolers and radiator mounting locations in the Corsair case.
I used the following applications in my tests:
Our case test cycle consists of the following phases:
- 10 minutes idling at the Windows desktop
- 10 minutes running the Prime95 Small FFTs CPU torture test
- 10 minutes running Prime95 and the Unigine Heaven GPU benchmark
- 10 minutes of cooldown time at the Windows desktop
Here are the results of my cooling tests, plotted over time:
And here are some minimum and maximum temperatures from each testing phase:
For the most part, the Define S hangs right with the Obsidian 450D in cooling performance. One case might best the other by a couple of degrees here and there, but neither one delivers a knockout on the cooling front. I’d be happy to rely on either of these cases to keep my system chilly.
The one area where the Obsidian 450D appears to be a better performer than the Define S is SSD temperatures with the Cooler Master Hyper D92 CPU cooler installed. Here, the 450D manages a seven-to-nine-degree C advantage. Strangely, that gulf doesn’t carry over to the Nepton 240M results, where the two cases pull much closer together. That makes me think my results are a bit of a fluke—we’ll have to re-test the 450D at some point to see whether those numbers remain consistent.
Here are the Define S’s noise levels at idle and load, along with the Obsidian 450D’s:
Subjectively, the Define S is quieter than the Obsidian 450D with an air cooler inside, probably due to the excellent numbers measured up top. At idle, and with the ModuVents installed, the case is 2-3 dBA quieter than the 450D in most areas, save for the right side. The plain plastic front panel allows more noise to escape in testing than the Define R5’s foam-backed front door, but the difference isn’t honestly that noticeable without looking at my sound meter.
Removing the Define S’s top panels to install a radiator allows more noise to escape from the top of the case at idle, putting it about even with the 450D, but it’s more polite under load. Installing the radiator at the front of the case would probably help even more, though it might hurt GPU temperatures.
One area where the Define S stands alone is in its suppression of hard drive motor noise. I’m not sure why, but I’m betting that the thumbscrew-secured 3.5″ drive sleds dampen vibration better than the slide-in units common in other cases. In fact, the Define S is the first case I’ve tested that hasn’t buzzed at all due to sympathetic vibrations from hard drive motors. A generally quiet case is no good if it occasionally makes a piercing racket, and the Define S is consistently quiet, not just most of the time. Bravo, Fractal.
Overall, I wouldn’t mind either of these cases under my desk, but I’d give a slight edge to the better-insulated Define S. The 450D’s more open front and top panels (and its extra 140-mm fan at the front of the case) can allow more system noise to escape, and hard drive motor vibrations can cause sympathetic buzzes and rattles in the 450D, as well.
As for the Define R5, it benches a little quieter all around than either of these cases, but it suffers from hard drive buzz, too, which mars its otherwise excellent performance. Until I reviewed the Define S, this buzz was par for the course, but Fractal has set a new bar for itself here. Hopefully the Define R6 features better drive noise dampening.
With its innovative interior design, the Define S feels something like the future of PC enclosures, not just another spin on the traditional ATX mid-tower. That’s a real achievement, given the march of relatively similar-looking cases through our labs lately. It’s exciting to see a company shake up the idea of what a tower case should be.
No case is perfect, and I do have a couple tiny complaints about the Define S. I still wish Fractal would include magnetic dust filters to replace the ModuVent panels up top when they’re removed. The bottom dust filter, while appreciated, is somewhat inconvenient to remove from the rear of the case with a system inside. Some builders might not find enough room for storage in this case, and those with optical drives are completely out of luck.
Those quibbles aside, the Define S is great. Its extra-spacious main chamber is a snap to work in, its cable-routing aids make clean builds easy, and its storage mounting arrangement is brilliant. The Define S also treats custom liquid-cooling loops as first-class citizens. While the Define R5 benches a little quieter than the Define S, the difference is honestly inaudible to me—and the S finally kills the sympathetic hard drive buzz that the R5 and many other cases fail to suppress.
At just $79 for the non-windowed version, the Define S is a spectacular value given its performance and builder-friendly features. For builds with only modest storage needs, the Define S is an excellent choice. It’s also the latest TR Editor’s Choice winner.