Value-seeking PC builders who would rather spend their money on internal components take note: With a mere 13 pounds of steel and plastic attached to its tempered-glass side panel, the MasterBox 600 ($99.99) provides little more than a pile of fans and some big radiator mounts to stand apart from a bargain-basement PC case. Our primary goals are to make sure that those fans flow well and aren’t too noisy, but we’re also keeping an eye out for quality and features along the way. The MasterBox is a reasonably good-looking ATX chassis for looks and air-cooling, but unless the design sings to you, we’d consider a slightly better value like the $79 Montech Air 903 Max or $109.99 Enermax StarryKnight SK30 v2 instead.Design: Making the Most of a Hundred BucksCooler Master did some fairly nice things with those minimal materials to help its case feel more stable, as seen in the pressed pattern of its steel mesh face. It covers three 140mm ARGB fans, behind you can fit a 420mm-format radiator up to 457mm long.
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Front-panel ports are located near the front of the top panel’s right edge, and feature two USB Type-A and one Type-C port on generationally correct cables. Forward of those, a four-pole headset jack combines stereo headphone and monaural microphone connections, a tiny plastic window reveals a hard drive activity LED, a repurposed reset button switches modes for an included ARGB controller, and a power button glows via its power LED backlight.
(Credit: Thomas Soderstrom)
Around back is a factory-supplied 120mm ARGB fan (mounted on slots that provide about an inch of height adjustment), plus seven expansion slots and a dual-pattern mount that allows power supplies to be installed with the lid facing either up or down.
A dark spot near the bottom rear corner of the right side panel (at photo left) is caused by a hump at the corner of its inner mounting bracket: This reviewer accidentally pressed a thumb-shaped dent into the adjacent metal while using said thumb to push the hump in. The metal, let’s say, is a bit flexible.
(Credit: Thomas Soderstrom)
All seven slot covers are disposable knock-outs that you break away to use. Any slots you intend to open up should have the breakouts removed prior to installing the motherboard, since the back edge of the motherboard tends to block these in (and you don’t want to scrape your board getting them out). You’ll only want to remove the slot covers that correspond to the position of your graphics (or other expansion) card, since the case doesn’t include any replacement slot covers. Good luck, there!
(Credit: Thomas Soderstrom)
There’s no dust-filtering provisions at the front of the MasterBox 600; the face is the dust catcher Perforations in the silver panels appear to be slightly smaller than those of the black portion.
(Credit: Thomas Soderstrom)
A laundry list of features fill the MasterBox 600’s motherboard tray, including “back plug-in” cutouts (its name for reversed cable connectors) that fit both ATX and MicroATX motherboards that have reverse connectors and extra cable passages for boards that don’t have that feature. Also on the tray: a giant hole that makes it easier to install the socket support plates that come with certain CPU coolers, grommets that help to conceal a portion of any cables inserted at the forward edge of ATX or MicroATX motherboards, and mounting holes that support 2.5-inch drives in five different places.Keen eyes will also notice several holes on the top of the power-supply cover that include (from back to front) three that match the typical locations of HD Audio, ARGB, USB, and front panel headers, one that aligns somewhat well with the PCIe power headers of most graphics cards, and a gigantic 3.5-inch gap that allows builders to tilt in a 420mm-format radiator.
(Credit: Thomas Soderstrom)
Builders who use the top panel as exhaust will find that the only dedicated dust filter is that of the power-supply inlet on the bottom of the MasterBox 600. Secured with tabs, it’s even more difficult to remove and reinstall that it is to get to. The inward-facing tabs and screw holes next to it secure an inner 3.5-inch drive cage.
(Credit: Thomas Soderstrom)
A look from the other side reveals the inner workings, including the triple-fan-mount top panel, the three front-mounted 140mm ARGB intake fans, the ARGB/fan hub, and the bottom-mounted 3.5-inch drive cage.
(Credit: Thomas Soderstrom)
The top panel can hold three fans only if they’re 120mm format, as there isn’t enough length to fit more than two 140mm fans. The mount has enough room for 360mm-format radiators up to 422mm in length, but radiator and fan combos greater than 52mm thick will hang past the motherboard’s top edge. Fortunately, the mount’s leftward offset provides around 44mm of horizontal clearance for thicker cooling combos.
(Credit: Thomas Soderstrom)
The MasterBox 600’s included hub supports up to four fans and up to five ARGB devices, as though Cooler Master wanted to leave room for builders to add one of its ARGB-equipped graphics-card braces. (Hmm…more about that in a minute.) As mentioned, the case’s “reset” button is repurposed to the hub’s ARGB controller, allowing builders to cycle through 14 patterns or shut off the light show by holding the button for a few seconds. Conversely, connecting the device’s external ARGB input to another ARGB source (such as the motherboard) switches it to passive hub mode, disabling its control features entirely.
(Credit: Thomas Soderstrom)
The lower drive cage supports the included 3.5-inch clip-on drive rails, but also has a set of holes in the same 2.5-inch pattern as those found on the motherboard tray. Located 8.7 inches (221mm) from the power supply mount and 89mm (3.5 inches) from the front panel, the cage can alternatively be moved forward 44mm (1.75 inches) to provide additional power-supply room by reducing radiator space.
(Credit: Thomas Soderstrom)
It’s not that we think anyone isn’t trying to provide the proper dimensions, it’s just that some things tend to get lost in translation (or in rounding). For example, the dimensions we provided above imply that one could remove the drive cage, add a radiator up to 44mm thick, put the cage back in, and still have around 264mm of space behind the drive cage for the power supply. Cooler Master insists that a radiator won’t fit when the cage is in the forward position, and that only 210mm of space is present with the cage slid forward, rather than the 220mm we measured with the cage slid back. While it’s likely that the 10mm difference between what Cooler Master stated and what we measured is meant to address the lip that protrudes inward from the outer edge of the case, the company’s assessment about cage position appears a little off.We measured thrice, and all three times concluded that in regard to space for this specific component at least, the buyer is getting a little more than what Cooler Master has said that they’re paying for.Building With the MasterBox 600Hoping to show off a little, Cooler Master shipped our MasterBox 600 sample with its Atlas ARGB GPU Support stand, linked earlier. We thought about using it, considered that it wouldn’t improve performance (I.e., no cheating), and decided to use it in today’s build. But know that it’s not part of the $99 price. (It runs about $50 alone.)
(Credit: Thomas Soderstrom)
Stuff we all get includes exactly enough hardware to install a motherboard, seven cards, two 3.5-inch drives, and two 2.5-inch drives: The bag’s 16 #6-32 screws can fill the nine holes of most ATX motherboards while leaving seven to fill the card bracket holes of the slot panel. The 3.5-inch drive rails are screw-free. That leaves eight M3-threaded studs and matching grommets to secure 2.5-inch drives into only two of the six mounts, though we’re sure that some determined builders could split this hardware up differently and make things work.
(Credit: Thomas Soderstrom)
Once the hardware is installed it’s time to connect cables: The ARGB/fan hub includes ARGB-signal, PWM-signal, and SATA-power inputs, and the rest of the case features a combined front-panel button/indicator LED plug, an HD Audio lead for the headset combo jack, a Type-E header for the Type-C front-panel port, and a 19-pin USB 3.2 connector for the two Type-A ports.
(Credit: Thomas Soderstrom)
Did you notice that the MasterBox 600 leaves enough open space to mount an Extended ATX motherboard, lacking only the three extra standoffs needed to secure the forward edge of the largest (13-inch-deep) variety? We did, and that means that you could mount one of the more familiar EATX-labeled boards without issue: So-called EATX gaming and HEDT (high-end desktop) boards tend to be only an inch deeper than the ATX model shown.
(Credit: Thomas Soderstrom)
And here’s our build with our test parts. Yes, the extra-cost ($50) stand does make the system stand out more than it would have otherwise.
(Credit: Thomas Soderstrom)
As for the card that the ARGB stand is holding up, it’s the now-familiar Verto Triple-Fan RTX 4070 Ti from PNY…
(Credit: Thomas Soderstrom)
It’s the new card we’ve settled on for our case-testing endeavors. Speaking of which… Testing the Masterbox 600: Showing Your Budget RootsHere’s a recap of the test components that we now use for testing PC cases…
The good news is that the MasterBox 600’s CPU cooling falls dead center between our best and worst cooling cases…
The not-so-great news is that the two that did worse were two different configurations of the same fanless case. Taking third place in voltage-regulator temperature, it climbs to second place in GPU cooling. Not bad. But we were disappointed to see the MasterBox 600 tie for last place in noise emissions.
All in all, the performance numbers reflect the price and the whole bill of lading.Verdict: Solid ATX for Inexpensive AirflowThe MasterBox 600 gives us all the space we’d need to mount a pair of big coolers, and all the fans we need to keep the interior cool without them. But the same thing can be said of the rival $109.99 Enermax StarryKnight SK30 v2. With little else to separate the two, the extra inch or so of radiator space that allows the MasterBox 600 to fit a 420mm-format radiator on the front panel might be its saving grace, depending on the build you are planning. But for a more pedestrian build, the SK30 is a slightly better value.
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