Software

As expected, the Nightsabre Wireless is fully compatible with iCUE, Corsair's capable yet resource-hungry software. In contrast to previous versions, iCUE 5 is modular now, decreasing its footprint in terms of RAM and background processes significantly. In addition, fewer driver packages (two in my case) are installed, and the infamous Corsair headset drivers are no longer automatically loaded, either. The UI is largely unchanged, which is why idiosyncrasies such as the distinction between software and hardware DPI or the lighting brightness slider being hidden under device instead of lighting settings continue to be around.

All options are available through multiple list entries. All buttons except the left main button can be remapped to mouse, keyboard, media, or macro functions. A shift function isn't explicitly present as such, but can be set up by utilizing the profile switching button mapping, though I've found iCUE sometimes crashes when doing that. CPI can be set for up to five color-coded stages, ranging from 100 to 26,000 CPI in increments of 1 CPI, and independently for the x and y-axis. Additionally, a surface calibration can be performed to lower the lift-off distance beyond the default level. Further LOD adjustment options are present under device settings, allowing one to choose between three presets (low, medium, and high). Polling rate adjustment (125/250/500/1000/2000 Hz) too is found under device settings, and the device is still restarted every time the polling rate is changed, which can get annoying rather quickly. Much like on other Corsair wireless mice, the polling rate has to be adjusted under device settings of the dongle if the mouse isn't plugged in, and somewhat irritatingly, the "wired polling rate" entry needs to changed. Under device settings, one also finds a setting called "Button Response Optimization." With it set to on, proper debouncing is performed, increasing click latency but reducing the likelihood of so-called slam-clicking. By setting it to off, debouncing is no longer performed, which lowers the click latency, but introduces slam-clicking. Lastly, angle snapping can be turned on or off.

Much like on previous versions of iCUE, setting changes are either saved to a software or a hardware profile, depending on which menu entry is chosen. On my system, the software has a RAM footprint of 329 MB on average when running in the foreground, along with considerable CPU and GPU time cost, which go down slightly when minimized to the system tray. Upon exiting the application, a single process with a RAM footprint of 5 MB keeps running.

Lighting

The Nightsabre Wireless has six physical and twelve logical lighting zones, the former of which are the are logo at the back, two strips on the top, two strips at the front, and a "grill" at the front. Without iCUE running, seven different lighting effects can be set up and saved to the on-board memory: Watercolor, Color Pulse, Color Shift, Rain, Rainbow, Rainbow Wave, and Visor. While running iCUE, a whole slew of lighting effects is available, including shift, blink, gradient, and pulse effects, many of which can be further adjusted in terms of transition speed, direction, and color palette, not to mention the ability to synchronize them with other Corsair devices. Of course, the lighting also can be disabled altogether.

Color accuracy and vibrancy are excellent throughout. Here's a short demonstration video in which I go through the Rainbow, Color Pulse, and Watercolor Spectrum lighting effects. Please note that brightness has been set to 100%:

Battery Life

Corsair states a maximum battery life of up to 65 hours in 2.4 GHz operation and up to 100 hours using Bluetooth, with illumination disabled for each. Corsair iCUE includes a basic battery life indicator, but instead of being percentage-based, it merely discriminates between descriptions (I only got to see "High"), which are essentially useless. As such, I'm unable to gauge anything.

Within iCUE, one can enable sleep mode and define after which period of inactivity sleep mode is entered. By default, this is set to 15 minutes, which is way too high and thus should be lowered to a more reasonable figure such as two minutes. Furthermore, one can enable Power Saving mode, which merely disables illumination.

Using the included USB Type-A to Type-C charging cable, I measured the charging speed during the constant current stage, which sits at around 0.472 A. The battery has a capacity of 560 mAh (3.7 V) and utilizes a 3-pin JST connector.