Cooler Master MasterMouse MM520 Gaming Mouse Review

Cooler Master's MasterMouse MM520 gaming mouse gets examined but is it one to avoid?

Manufacturer: Cooler Master
13 minute read time
TweakTown's Rating: 79%

The Bottom Line

The MM520 is affordable, and on paper it appears to be terrific. However, the overpowered nature of the sensor is a bit off, and the fact that logos and patterns throw off the sensors ability to track properly leaves us with little option but to look for something better!

Introduction, Specifications, and Pricing

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Cooler Master has seemingly killed the Storm series of peripherals in favor of names like Master and Maker in titles these days, but this is no indication that they are not above revisiting older ideas. What was once referred to as the CM Storm Spawn has undergone a transformation, which brings it up to today's level of what is expected in a gaming mouse. At the time, the Spawn was well appointed, but by today's standards, it just would not fly, no matter how attractive that ruby red top cover was. With just one glance, we find that we can see at least eight things about the design which have been improved upon, and should make the resurgence of the Spawn a success for Cooler Master.

The Spawn did have quite a few limitations. It came with no LED lighting at all for starters, which has been addressed. The DPI was quite low, ordinary Omron switches were used, the sensor is a bit long in the tooth now, the onboard memory was not all that great in size, the scroll wheel was cheap looking and made of plastic, and even the weight changes with the newer version. All of these things fall into categories of improvements or fulfilling the desires based on the latest trends in what the market bares. Cooler Master may, in fact, be reissuing a product that did very well for them in the past, but it is easy to see they are not asleep at the wheel, trying just to put lipstick on the same old pig here.

Today we have a look at one of three mice to be introduced into the MasterMouse lineup. The reason that three mice were presented at the same time is that Cooler Master is striving to suit all grip styles, and the one we have now is built with the intention to be form fitted to claw grip and palm grip users. With more than enough changes afoot to keep the masses happy, we feel we should get right down to brass tacks and see just what the MasterMouse MM520 from Cooler Master delivers, and find out if it indeed should be your next mouse.

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The MasterMouse MM520 also goes by the model number SGM-2007-KLON1, and as we just mentioned, it is intended to be used by claw and palm grip gamers. The MM520 is made of plastic, and there is a grip pad on the right made of rubber, but on site, they also make mention of using PBT plastic for the main buttons, so there is no wear over time. Rather than red, the color of the MM520 is black, M14 black to be precise. Dimensionally, the MM520 measures in at 78.5mm wide, it is 118mm long, it is 29.5mm tall, and without the cable, it weighs only 101 grams. To help out with longevity, where many others offer only a year of coverage, Cooler Master backs the MM520 with a two-year warranty.

The mouse also sports RGB LEDs which are shown to deliver over sixteen million colors, which is a huge leap from the Spawn, with no LED illumination, at all. The sensor used is the PixArt PMW-3360 optical sensor and will top out at 12,000 DPI. Adjustments can be made in 100 DPI increments, and there are four DPI levels which can be set for on-the-fly changes. The sensor is also capable of tracking movement at 250 IPS at fifty times the force of gravity, the LOD is set to 2mm, the polling rate is 1ms, there is no built-in acceleration, and angle snapping can be turned on or off. In control of it all is an ARM Cortex M0 32-bit MCU, which provides five profiles for storing customizations, and even delivers 512KB of onboard storage. There are six buttons in total, two of which are backed with twenty million click Omron switches, and lastly, the cable is rubberized, it is 1.8 meters in length, and does come with a gold-plated USB 2.0 connection.

At a glance, and after progressing through the specifications, we feel that the MasterMouse MM520 has much going for it, and Cooler Master could have just as easily asked somewhere in the range of $80 for this device. However, this is not the angle they wished to pursue. When it comes to obtaining the MM520, all you will need is $49.99 at the ready to obtain one, and we also see that pricing is the same no matter where we looked to obtain it from. Knowing what we do so far, you will be hard-pressed to find a mouse similar in design, with this amount of features and functionality, at this price point. The Cooler Master MasterMouse MM520 RGB Gaming Mouse is already off to a great start, but let's get to the meat and potatoes of it all, and see if everything stands up to the rigors of testing.

Chad's Peripherals Test System Specifications

Packaging, Accessories, and Documentation

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On a matte black box, we find a top view of the MasterMouse MM520 dead center of the panel. At the top is the Cooler Master logo and tagline, with a notation to three zones of RGB lighting. Under the product name at the bottom, we also see that Cooler Master intends this mouse to be used by claw grip users, even though palm grip users may use it comfortably as well.

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The front panel of the box is held closed by a pair of Velcro pads. Opening the front of the box shows us the mouse under plastic on the right side, and to the left are simplified specifications for the sensor and a descriptive tale of why the MasterMouse MM520 came to be.

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On the next panel, we find much of the same information at the top about the product; the image has been taken of the left side of the mouse this time. Also, at the bottom, is the product sticker with the model and serial numbers presented on it.

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Around to the back of the box, we see yet another angle view of the MM520 to start things off. Following that, we see features like the claw grip design, the 12,000 DPI, its fully programmable nature, the rugged quality, and RGB illumination, which is then repeated in various languages.

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The last panel states that this is a gaming mouse and that its name is MasterMouse MM520. The information is then translated more than twenty times to cover all of the markets Cooler Master products sell in.

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Inner packaging is as good as it gets. Using two formed sections of plastic, one above the mouse, and another to support it, not only protects the mouse while in transit but also offers room under it to store the cable and any goodies that might come with it.

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In this instance, the only thing that comes with the mouse is the guide. Inside you will find a button overview, the specifications, and the package contents. On the reverse, there are two images of the mouse, which flank an entire page of legal information and terms of the warranty.

Cooler Master MasterMouse MM520 Gaming Mouse

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The left side of the MM520 offers a convex shape for the thumb, made of textured plastic. At the top edge are two shiny buttons, and near the back, at the bottom, we can see part of one of the RGB LED zones.

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From the back, we can see the offset shape that leans left, but at the same time, the right side drops away for better ergonomics. Between the body lines is the Cooler Master logo with a ring around it which is RGB backlit, and we can see the entire strip at the bottom now too.

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The right side of the MM520 drops off in two stages. The first part, higher up on the side, is where the ring finger rests. The lower section is a bit wider and has a rubber pad inserted into the body, which gives the pinky finger added grip when it comes time to lift this mouse.

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The view from the front of the MM520 shows that the main buttons nearly come together in the middle and that each of the buttons is concave to help fit the hand better. The nose of the mouse is inset a bit, and the cable exits the MM520 in the center.

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Between the main buttons are the rubber covered scroll wheel, which is also the third RGB LED zone. Behind it is a single button, and by default, it is set to allow you to swap through four levels of DPI settings.

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Flipping the MM520 over, we can see that it glides upon three larger PTFE pads, one at the front, one at the back, and one under the wing on the right side of the mouse. The eye of the sensor is centered, and if you happen to pitch the box, the serial number is found on the sticker here as well.

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The 1.8 meters of cable is covered in a rubberized sleeve and is bound currently with a twist tie. Near the end of the cable is an in-line choke, and while the connector has the Cooler Master log on it, we also see the plastic inside of the gold-plated USB 2.0 connection is purple.

Inside the MasterMouse MM520

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Two screws at the heel of the MM520 allow us to get inside to have a look around. In the top half, we see a weight which is 10 grams and helps to explain the weight increase from the Spawn. The lower half is where all of the magic happens in the MM520.

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We do not see any brand marking on the segmented scroll wheel switch, but under the left button is an Omron switch. It is the D2FC-F-7N(20M) variety, it requires medium force to use, and the click coming from the switch is crisp and solid sounding.

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The buttons on the left side of the mouse, used to move pages forward and back, are backed by pad switches on pillars. Again, with these switches, there are no names present, just the "14" engraved into the metal frames.

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Used to back the DPI selector button, we find a non-descript brown pad switch. More force is required for use than the Omron switches, and while there is a click when pressed, it sounds hollow and not as crisp as others.

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The PixArt PMW-3360 is what is in control of tracking all movements, and by itself cannot deliver the DPI offered in the MM520. Cooler Master uses software to bolster the abilities of this sensor, providing 12,000 DPI for those who wish to try to control the mouse at that level.

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Boasting 512KB of onboard memory, this Holtek HT32F52352 chip not only does that but is what manages all traffic and allows for customizations. This is a 32-bit ARM Cortex M0 MCU, and it has more than enough grunt to run everything the MM520 brings to the table.

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The last image from inside of the mouse is that of the second Omron switch used under the right click button. Used for the click function to the scroll wheel, we find a Kailh brown switch, which is firm, and the click is crisp.

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Once powered, the go-to colors on the MasterMouse MM520 is purple. The zones around the back, the logo on the heel, and the scroll wheel near the front can all be addressed via software so that the aesthetics can be changed to suit any environment.

The Software

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You will need to download and install the software, but once done and opened, this is what you see first. The main Control tab has a few options to browse through, but at this time we are looking at the key assignments. Using the numbers on the left or the drop-down menu on the right, you can select just about any function to set from multimedia, on to keyboard controls or Macros.

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TactiX is something new for Cooler Master and is similar to EasyShift+. What this allows for is a second layer to be programmed to the mouse. You need to assign the DPI button to be used for TactiX, and one that is done, it works like the Function key on a keyboard and can be held along with pressing other keys to give multiple functions to each button.

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The LED tab is where one would address the lighting. On the left are two images, where you can see the lights you are about to change. On the right are RGB sliders, as well as places to select colors on the right of it. At the bottom are eight ways in which the lights can be set to modes or turned off, and keep in mind, all of these settings so far, can be addressed to one of the five profiles at the bottom.

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Under the heading of the sensor, we can go in and change the four DPI level sliders to suit our needs, and the X and Y axis can be set individually as well. This is also where you will go to change the polling rate, angle tuning, angle snapping, LOD, and even set the software for use with specific mouse pads.

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The last tab under main controls allows us to change the OS sensitivity of the movement, we can also change the double-click speed setting, and there is one more slider to change the button respond time.

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The Macro editor is basic, but there is enough to get by. After naming a new Macro, you click start. A window pops up asking if we want to record delays as they are used, insert a set time between presses, or use God Mode, with no delay between them. The Macro commands will appear at the right, and the only option to edit is to use the insert drop-down to add commands or remove them.

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There is also a repository for profiles called the Library. After messing about with the software, you may want to save an entire profile, and here is where it is done. The list at the left will populate, and allow users to house as many profiles as they want to, and conveniently switch which is used on the five available slots.

Gaming and General Impressions


The MM520, being software enhanced to reach 12,000 DPI is a bit wonky. The sensor is very touchy, and for normal gameplay, we could not handle much more than 4000 DPI. The cursor never wandered or jittered, but going past 4000 DPI had us wandering all over the place with little control or accuracy. Sadly, we found another issue with the optical sensor as well.

Using multiple mouse pads to test out the issue, we found that the MM520 does not like being moussed over any paint or imagery on the pad. This can be a huge downfall for the MM520, as many like to have fancy looking mouse pads. If you are going to jump on this mouse for its comfort and programmability options, which are all fine in their own right, we do suggest that you buy a solid colored surface to use it on.

Windows and Productivity

Using the mouse every day is comfortable and stress-free. However, we do still find that surpassing the midrange of DPI leads to control and accuracy issues. When editing images, it slowed us down considerably using higher DPI settings and even made it tough to double click correctly on icons on the desktop.

Using it to surf the web or to open emails was fine, but something is going on with this product, where we feel Cooler Master put the PixArt sensor on a diet of steroids; it is unlike any other optical sensor that boasts 12,000 DPI. While we were able to get by with the grind, we do feel that if accuracy is demanded, which it should be, the MM520 will have to be used at low DPI, negating the fact it offers what it does.

Final Thoughts

The MM520 is a huge advance on what the Spawn delivered those many years ago. Cooler Master kept the shape, but that is about it. The blacked-out aesthetics are nice, and offering three zones of RGB LED illumination takes this mouse into the current day. Updating and upgrading every bit inside of the mouse isn't a total disaster, but we do wish they would work on the DPI algorithm to deliver better control throughout the DPI scale. However, we still have the fact that with five profiles and TactiX aiding the functionality, across the five profiles, you can set up over fifty functions to the MM520 without ever having to go back to the software. With as much as the software can do, we do wish that we had individual control of the LED zones, and we do wish the Macro Editor portion was a bit more involved.

With so much to like visually, and by looking at the specifications, we do feel there are some issues we cannot overlook. For starters, the fact that the sensor has issues on colored pads is a bit of a downer. Any sensor should work on any surface at this point, and moving over a logo or funky pattern playing up with the tracking is just something we never expected to find. Offering a mouse with 12,000 DPI is all the rage right now, whether the sensor is laser or optical. That being said, Cooler Master has tweaked something too far in our opinion. Other mice with this level of DPI range do not get so dramatic in the middle of the scale, and we feel that it will take days, maybe even weeks before muscle memory is set for this oversensitive mouse.

There is one saving grace to the whole thing though, and that is the cost. If you feel like trying your hand on the MasterMouse MM520 or just don't want to trust what we are telling you, at $49.99, it won't cost much to try it out. While the shape is perfect for claw and palm grip users, the mouse looks nice on the desk, and the software is thorough, we sadly have to say to you that you may want to look elsewhere for your next mouse. If you have bionic reactions and are up for a challenge, by all means, give the MasterMouse MM520 Gaming Mouse a try. For us, we are going to say pass, and move onto something with better controllability and accuracy.

Chad's Peripherals Test System Specifications


The Bottom Line: The MM520 is affordable, and on paper it appears to be terrific. However, the overpowered nature of the sensor is a bit off, and the fact that logos and patterns throw off the sensors ability to track properly leaves us with little option but to look for something better!

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Chad joined the TweakTown team in 2009 and has since reviewed 100s of new techy items. After a year of gaming, Chad caught the OC bug. With overclocking comes the need for better cooling, and Chad has had many air and water setups. With a few years of abusing computer parts, he decided to take his chances and try to get a review job. As an avid overclocker, Chad is always looking for the next leg up in RAM and coolers.

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