After Razer, EVGA, Corsair, and ASUS, MSI joins the ranks of gaming mice capable of true 8000 Hz polling with the Clutch GM51 Lightweight. The general benefit afforded by 8000 Hz polling is twofold: For sensor motion, latency will be slightly lower and tracking generally smoother, which typically only becomes noticeable on high refresh rate monitors (240 Hz and up); for click events, the possible minimum latency likewise is slightly lower. The GM51 is a USB high-speed device, and therefore natively capable of polling rates above 1000 Hz, and since the GM51 utilizes PixArt's PAW3395 sensor, the sensor framerate likewise is sufficiently high to fully support a polling rate of 8000 Hz. In my testing, I've found that the GM51 indeed averages the intended polling rate target values, albeit with a catch: On polling rates below 8000 Hz, periodic bursts of off-period polls can be observed, whose magnitude increases the lower the polling rate is. Since most people may be inclined not to use 8000 Hz all the time for compatibility reasons, this presents an issue, as 1000 Hz in particular is far from stable. This polling instability aside, sensor performance on the GM51 is on a good level: CPI deviation is appreciably low, general tracking fine, and motion delay just as low as it should be on an 8000 Hz mouse. Since there is no smoothing across the entire CPI range, opting for higher CPI steps to ensure that the 8000 Hz polling is fully saturated is possible without a latency penalty, which is a good thing. The GM51 also allows for turning MotionSync on or off, though on the latest firmware, this has no effect since MotionSync is permanently enabled.

Click latency is disappointing on the GM51. On paper, 8000 Hz allows for incredibly low click latency, as previously seen on 8000 Hz mice such as the Razer Viper 8K and DeathAdder V3, Zaunkoenig M2K, Atompalm Hydrogen, or ASUS ROG Chakram X, which all sit at around 0.1 ms click latency. On the GM51, I've measured a click latency of 5.4 ms, which not only falls short of the mentioned 8000 Hz mice, but even of most 1000 Hz mice. Hence, a good part of what makes 8000 Hz interesting from a latency perspective in the first place simply isn't present on the GM51. The ability to witness this mediocrity in real-time by virtue of NVIDIA Reflex support therefore is hardly a selling point.

These technical deficiencies aside, the GM51 is not a bad mouse. At 74 g, the mouse isn't particularly light, but still acceptable given its size and generous use of RGB lighting. The GM51 shares its tooling with the GM51 Wireless, which somewhat limits the efficiency of the design, but on the flip side, the build is quite solid, as there is no rattle when shaking my sample, and creaking or flexing are kept to a minimum. That said, when applying pressure laterally, actuating the side buttons is possible even without using excessive force, which is somewhat disappointing. Compared to other 8000 Hz mice, the GM51 has a surprisingly flexible cable, which is remarkable in that 8000 Hz poses a greater challenge when it comes to signal integrity than regular 1000 Hz. The Razer Viper 8K cable, for instance, has particularly strong shielding, which negatively affects flexibility, whereas the Zaunkoenig M2K cable is shorter than most others. The cable of the GM51, on the other hand, is plenty flexible and almost 2 m long, yet I haven't been able to detect any signs of poor signal integrity at 8000 Hz. Lastly, white-dyed pure PTFE feet are used on the GM51, which afford good glide.

When it comes to the main buttons, MSI has opted for switches from Omron, which provide a very snappy and pleasing button response without being overly heavy. Of particular note is that, despite a split-button design being used, lateral button movement is minimal, even when provoked. That said, button feedback on my unit isn't entirely uniform between the left and right main buttons. The side buttons have been outfitted with Huano switches and likewise are of good quality, as pre and post-travel are fairly low, although actuation on the back button isn't entirely even, leading to a slightly mushy response. As a result of the GM51 being a very tall mouse with a notably raised left side, the placement of the side buttons is far from optimal, however. Those who prefer actuating the side buttons by simply rolling their thumb across will find the side buttons to be entirely out of reach, which is further complicated by their design. While the side buttons on most other mice are mostly flat or level, the ones on the GM51 stick out quite a bit and are shaped like a triangle, which serves no purpose on a functional level. The scroll wheel at least is quite good, with appreciably low noise levels and decent tactility, but the scroll wheel click presents another issue. Due to its actuation being far too light, unintentionally actuating the wheel click can happen quite easily while scrolling, which is highly undesirable, especially for games. For what it's worth, on my sample of the GM51 Wireless, which utilizes a very similar switch for this button, actuation isn't anywhere near this light, so this could be due to the switch on my unit being either at the lower end of tolerances or beyond it. In any case, assuming my unit is generally representative of the average of other units, this presents a real issue.

MSI Center is the software of choice for the GM51, and continues to be a major nuisance. Regardless of whether MSI Center is currently running, a whole host of processes is continually running in the background, even if MSI Center isn't set to start with Windows. Resource usage is fairly high, and infinite loading screens and frequent crashes are commonly encountered when working with MSI Center. Of particular note is that, despite the PAW3395 sensor allowing for CPI adjustment in increments of 50, the UI artificially restricts this to increments of 100. Granted, CPI deviation is low on the GM51 and adjustment therefore not strictly required, but why limit what the sensor is perfectly capable of? Another challenge presented itself in that installing the Mystic Light module, which controls the RGB lighting, wasn't possible since it simply didn't show up within MSI Center, and nothing I did on my end could change that. Eventually, MSI doing something on their end solved this, but it certainly underlines that MSI Center tends to be a messy affair. For the record, the media buttons on my keyboard also stopped worked correctly after installing MSI Center for a second time.

In summary, the Clutch GM51 Lightweight fails to leave a good impression. Click latency is too high for an 8000 Hz mouse, polling is not stable almost across the board, and there are further concerns related to the scroll wheel switch and software. Furthermore, the GM51 becomes an even less compelling offer when considering the fact that the vastly superior Razer DeathAdder V3 is available for the same $69.99 the GM51 retails for.