Home / PC H/W Reviews / Core PC Components / PC Enclosures/Cooling Reviews / COOLER MASTER MASTERBOX K500L PC Case Review


  1. About the Masterbox K500L…
  2. PC Case Overview- External
  3. PC Case Overview- Internal
  4. Test Setup,Testing Method and Results
  5. Conclusion
  6. Online Purchase Links
  7. View All

Disclosure: The Masterbox K500L PC case is loaned by Cooler Master and returned after the review is completed.

About the Masterbox K500L…

The Cooler Master Masterbox K500L is a PC case expected to be somewhere before or between the Cooler Master Masterbox MB500, depending on what you want and can pay for. The comparison is made with the Masterbox MB500 because that’s what it is. The main difference is the lack of additional features and different front panel design. There are also some minor differences such as the installation of the front panel I.O- beauty is in the eyes of the beholder.

Packaging and Contents

Nothing really new for a case of such class- a brown box with specs listing. The K500L is protected by two foam blocks and a plastic wrap. The contents are bone-dry bare basic- just screws and cable ties. You get a couple of reading materials and that’s it.


Product Name MasterBox K500L
Product Number MCB-K500L-KNNN-S00 MCB-K500L-KANN-S00
Available Color Black
Materials Steel, Plastic
Left Side Panel Steel Acrylic
Dimensions (LxWxH) 491 x 200 x 451mm 491 x 210 x 455mm
Motherboard Support ATX, Micro-ATX, Mini-ITX
Expansion Slots 7
Drive Bays 5.25″ N/A
3.5″ HDD 2 (Max. 2)
2.5″ SSD 1 (Max. 6)
I/O Port USB 3.0 x 2, Audio In / Out
Pre-installed Fan(s) Front 120mm x 2 Red LED fan
Rear 120mm x 1 black fan
Fan Support Front 120mm x 3 / 140mm x 2
Top 120mm x 2
Rear 120mm x 1
Bottom N/A
Radiator Support Front 120/140/240/280mm
Rear 120mm
Clearances CPU Cooler 160mm
PSU 180mm
GPU 400mm
Cable Routing Behind MB Tray 15-23mm
Dust Filters Front, Top, Bottom
Power Supply Bottom mount, ATX
EAN Code 4719512070147 4719512071359
UPC Code 884102042652 884102043857

There are two sub-variants in the Masterbox K500L- naturally the second is with the sidepanel. Not sure why it has the extra 5mm height. The case allows you to install radiator size up to 280mm towards the front.

PC Case Overview- External

The Masterbox K500L and the MB500 is the same frame with a different front panel option. The Masterbox K500L does not have an RGB controller and the option between full metal and transparent sidepanel option. For some, this would be better since the RGB controller adds up additional cabling. It depends on the person’s preference. But if you choose between the two case, there’s no real difference.

Front Panel Overview

The MB500 and the K500L have the same front I/O options. The MB500 has Reset and Power switches with its respective LED indicator and the HDD indicator, the 3.5mm audio jack connectors and the dual USB 3.0 ports. Just below that there’s a small vent where it faces a part of the top 120mm fan mount. The front mesh is in the same location as on the MB500, but with a different design. It provides ample ventilation for dual 120mm fans installed on the lower side of the front panel.

Rear Panel Overview

The rear panel allows 120mm fan only. All the seven PCIe slots are vented with no dividers in between. These come in the way of graphics cards that are typically dual I/O slot typically. The sides are vented. The removable PSU frame is in place using thumbscrews.

Top/Base Panel Overview

The top panel has a removable magnetic air filter while the base has a basic mesh. While the top panel cleaning is hassle-free, the filter for the PSU fans underneath needs a little thought. Any case, the only way around is just to tilt the system and remove the filter and clean up the area & the filter.

Top Panel Area

The top panel allows mounting of two 120mm fans. the air filter is on the outside and easily removed because of the magnetic strip.

PC Case Overview- Internal

What’s there to say? I am beating a dead horse at this point by mentioning MB500 framing. Due to the variable cable management space and the PSU shroud + HDD bay mount, such case designs are made keeping mid-end gaming PCs with max an 11″ GPU, a 240mm AIO liquid cooler an SSD and/or a single HDD. It makes sense to choose a semi-modular power supply with flat modular cables. They are reasonable semi-modular power supplies easily available for a while, such as the older Cooler Master G450M. For all steel sidepanel, I would not have included the power supply shroud to have it more open. It needs something to separate itself from the Masterbox MB500.

Motherboard Area

The maximum support for this case is the ATX form factor. There are cut-outs on the right side for the main cables like the 24-pin ATX and the GPU’s pin connectors. Keeping up with the traditional irrespective of its price segment, the stand-offs are not pre-installed.

PSU Shroud Area

The PSU shroud looks redundant as this sub-variant does not have a transparent side panel. The PSU shroud is riveted. There are two SSD mounting cut-outs but the case has only one SSD mounting frame. There are two more SSD mounts on the vertical area at the motherboard tray, towards the front panel. The lower portion of the case hides the power supplies and the 2x HDD tray where you can install 2.5” SSDs, too.

Unfortunately, the PC case inherits some flaws of the MB500. While the SSD cable management holes on the shroud act as a way to route through the front panel and lower USB header connections, there are no connectors towards the lower left side of the motherboard tray, typically where front panel audio and other front panel cables are connected.

Front Panel Fan Access

The front part of the PSU shroud has the cut-out to slip in a liquid cooling radiator. The case allows 240/280mm radiator installation only towards the front and 120mm radiator mount at the rear panel. The Masterbox MB500 does have 360mm radiator support up to 50mm thickness without fan on paper. The reason being the way K500L’s front panel is installed on the case which I’ll mention in the coming pages.

Apart from the front LED fans, there is an additional LED on the front panel. Thankfully you can unplug the cable to separate the case from the front panel shroud by unclipping this connector.

Rear Panel Area

All the PCIe slots use hex screws. The rear fan height can be adjusted. No surprises here. Having these hex screws on a higher priced MB500 is exotic.

Cable Management Area

There are plenty of cable tie loops behind the motherboard tray. If you have a semi-modular PSU with flat modular cables, you should be fine. There’s a large enough cut-out for the CPU socket area.

Included Case Fans

The Masterbox K500L uses three CM DF-12025-12-RFLN Rifle Bearing fans- front two with LEDs and rear for exhaust. The same model is used by other companies like Silverstone and NZXT.


There are two Molex connectors for powering up the fans and the LED on the front panel. The three- 3 pin to Molex connector is for the front-facing fans while keeping the third reserved if you choose to get a third front intake fan. But truth be told I would have appreciated if the case used the SATA connectors. Reason being in typical systems with semi-modular power supplies, you end up using Molex cables. Just how many components use Molex now?

Installation Impressions

Technically, you can install the 360mm radiator, but the issue is the front panel installation. To install the top 120mm fan, you need to remove the front I/O to gain access to the top two mounting holes and later re-mount it. This isn’t the problem on the MB500 as its front I/O panel is mounted above its frame. The ventilation area below the front I/O should provide some legroom to pull air in.

HDD Tray Mounting

This is the better HDD tray compared to the one provided in a premium PC case the Masterbox H500P. This is a retractable design where you can install the HD comfortably while the one in the H500P is where its expected to bend the HDD tray and manage to secure the HDD on it. Why isn’t this on the H500P??

Setup Images

The installation for the K500L is no different. The EPS 12V cable needs to be split and pushed through the case’s cable management hole. The cable management is functional, but it would be nice if there was a cut-out for the lower left areas. The lower area does have a habit of collecting cables especially when you install the HDD and have more connectors per cable. This was the case with the MB500 which also has the RGB controller.

The top panel wouldn’t allow you to install the radiator because of restricting depth and height with the motherboard tray. This case would be nice if it had a bit more depth and height. The case would not allow you to install any larger air CPU coolers above Noctua NH-U12S. The NH-U14S was installed on the MB500 but you cannot use the side panel.

Cable Management

The cable management works as long as you are using at least a semi-modular power supply with flat modular cables. All fits the way it should. There are no problems. Since the frame and the components are the same, you can check out the MB500 cable management with the Thermaltake Smart DPS-G Gold 750-watt power supply.

Excerpts from MB500 review:

With the Gigabyte Z97 Gaming GT ATX motherboard with the Core i7 4790K and a Noctua NH-U12S CPU air cooler, a SanDisk Extreme II 240GB SSD and a WD 3TB Red EFRX HDD for storage, and the Thermaltake DPS G Gold 750w semi-modular flat cable power supply, the system looks full. It is a good practice to have some additional height and depth for the motherboard. You’ll not have compatibility issues with a graphics card, such as the AORUS RX 580 XTR 8G OC which is used here with the Cooler Master GPU stand with a magnetic base. For AIO compatibility, I’ve used the CM Masterliquid ML240R RGB AIO cooler which will be released and have its review out.

Personally, I would like to see full mesh frontal on the Masterbox MB500.  I’ve reinstalled the CPU fans towards the top of the front frame. The lower fan installation may have its airflow somewhat restricted due to the shroud. It would be advisable to have an additional 120mm fan for the lower section, especially if you have mechanical HDDs installed at its base. Another reason I prefer such installation is the front panel. Even if its upper side does not have any grills, its shaped in a way where there is some distance between it and the fans. While the fan facing the grill pulls in the air for the graphics card, the upper mount fan should help to circulate the air intake through the memory stick and the CPU cooler.

The core system used to test the case is as follows:

Operating System Windows 10 Pro 64-bit
Processor+ Cooler Intel i7 4790k + Noctua NH-U12S
Motherboard Gigabyte Z97X-Gaming GT
RAM 8GB Kingston DDR3 HyperX
Primary Storage 240GB SanDisk Extreme II SSD
Secondary Storage 3TB WD Red WD30EFRX
Power Supply Cooler Master GM450
PC Case CM K500L

Conditions and Components used during testing

Room Conditions:

Room sound level: 49.7 dB
Room temperature: 31c

System setup:

GPU FAN @ 75% (3144 RPM)

CPU fan speed @ 100%
CPU_FAN 1: 1461 RPM
CPU_FAN 2: 1461 RPM

Case fan speed @ 100%

Temperature and sound levels are recorded 36 hours after assembling.

Performance Testing- Sound and Temperature

Sound Testing

Temperature Testing

Almost inheriting everything from the MB500…

The only odd part in this is the installation for the front 120mm fan. Also, CM could have corrected by providing additional height and depth to provide more space, such as cut-outs for the lower-left section for the motherboard I/O ports and easily pushing in EPS 8 PIN ATX connector. SATA power connectors could have been provided instead of Molex and even a removable shroud. Depth helps to provide more space behind the motherboard tray. Would you be upset about non-compatibility of 140mm CPU coolers? Its the same reasoning as who would consider mounting a 360mm radiator in it! But the upper front panel fan installation requires you to remove the I/O to gain access to its fan mounts.

To distance itself from the Masterbox MB500, the Masterbox K500L could have been an all mesh design.

HDD Bay Area

The PC case is good enough for mid-end performance PC components as long as you are sticking with semi-modular power supplies with flat cables as a bare minimum. This case (or cases) has PSU clearance of 180mm so keep cabling clutter to the minimum. Regardless there would be a nuisance when you use both the HDD trays. The distance between them is minimal and all the cable go through that section. A shroud-less design for the KNNN sub-variant makes sense because there is no transparent sidepanel.

Would you buy it?

The case is functional. It has limitations but within a certain choice (a very wide choice) of components, it houses everything you need to. The issue for Cooler Master is the options out there within this price segment. Anybody looking for a case within this price segment would have preferred a non-flash and larger PC case.

  • Frontal Ventilation
  • Multiple mounting alternatives for SSDs
  • No glossy plastic
  • Magnetic mesh filter
  • Molex connectors!
  • Needs more depth and height
  • Needs better air filter design for the PSU
  • Cable management will be cramped with non-flat and semi-modular power supplies

India US UK
₹ 6,605/- NA NA

COOLER MASTER MASTERBOX K500L PC Case Review from hardware

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