Sensor and Performance

The Rival 3 is equipped with the PixArt PMW3311. According to specifications, the 3331 is capable of up to 8500 CPI, as well as a maximum tracking speed of 300 IPS, which equals 7.62 m/s. Out of the box, two pre-defined CPI steps are available: 800 and 1600 CPI.

CPI Accuracy

"CPI" (short for counts per inch) describes the amount of counts registered by the mouse if it is moved exactly one inch. There are several factors (firmware, mounting height of the sensor not meeting specifications, mouse feet thickness, mousing surface, among others) which may contribute to nominal CPI not matching actual CPI. It is impossible to always achieve a perfect match, but ideally, nominal and actual CPI should differ as little as possible. In this test I'm determining whether this is the case or not. However, please keep in mind that said variance will still vary from unit to unit, so your mileage may vary.


I've restricted my testing to the four most common CPI steps, which are 400, 800, 1600, and 3200. As you can see, deviation is decently low, but fairly inconsistent, which is a good result.

Motion Delay

"Motion delay" encompasses all kinds of sensor lag. Any further sources of input delay will not be recorded in this test. The main thing I'll be looking for in this test is sensor smoothing, which describes an averaging of motion data across several capture frames in order to reduce jitter at higher CPI values, increasing motion delay along with it. The goal here is to have as little smoothing as possible. As there is no way to accurately measure motion delay absolutely, it can only be done by comparison with a control subject that has been determined to have the lowest possible motion delay. In this case the control subject is a G403, whose 3366 has no visible smoothing across the entire CPI range.


First, I'm looking at two xCount plots in order to determine whether there is any smoothing present, which would be indicated by any visible "kinks," and if there is, at which threshold it kicks in. As you can see, no such kinks can be observed at 3500 CPI, whereas at 3600 CPI, it's plainly visible. We can therefore conclude that the smoothing kicks in at and above 3600 CPI, which is considerably sooner than on the 3331-equipped ROCCAT Kain 100 AIMO. What we can also see is SPI timing having enormous amounts of jitter, which is indicated by the number of dotted lines. The Kain 100 did much better in this regard as well.


In order to verify the results from the xCount plots above, I'm looking at xSum plots generated at 3500, 3600, and 8500 CPI. The line further to the left denotes the sensor with less motion delay. At 3500 CPI, motion delay is identical; at 3600 CPI, motion delay is roughly 3 ms; and at 8500 CPI, motion delay is still 3 ms. To sum it up, smoothing is very minor and only kicks in at 3600 CPI.

Speed-Related Accuracy Variance (SRAV)

What people typically mean when they talk about "acceleration" is speed-related accuracy variance (or short SRAV). It's not about the mouse having a set amount of inherent positive or negative acceleration, but about the cursor not traveling the same distance if the mouse is moved the same physical distance at different speeds. The easiest way to test this is by comparison with a control subject that is known to have very low SRAV, which in this case is the G403. As you can see from the plot, no displacement between the two cursor paths can be observed, which confirms that SRAV is very low.

Perfect Control Speed

Perfect Control Speed (or PCS for short) is the maximum speed up to which the mouse and its sensor can be moved without the sensor malfunctioning in any way. I've only managed to hit just below 4 m/s (which is within the proclaimed PCS range), at which speed no sign of the sensor malfunctioning can be observed.

Polling Rate Stability

All four possible settings (125 Hz, 250 Hz, 500 Hz, and 1000 Hz) look nice and stable.

Paint Test

This test is used to indicate any potential issues with angle snapping (non-native straightening of linear motion) and jitter, along with any sensor lens rattle. This time around, I'm testing four CPI values: 1600 CPI as a general use baseline; 3500 CPI as the highest CPI step without any smoothing; 3600 CPI as the first CPI step with smoothing; and 8500 CPI as the highest CPI step with smoothing. As you can see, no issues with angle snapping can be observed at any of the tested CPI steps. 1600 CPI already shows minor jitter. At 3500 CPI, jitter is increased, but still under control, and at 3600 CPI, where smoothing is first applied, it is only marginally reduced. Finally, at 8500 CPI, jitter is very high. Furthermore, there is no sensor lens rattle.

Lift-off Distance

The Rival 3 does not support adjusting LOD. The only available (default) setting is high as it does track at a height of 2 DVDs, but not at a height of 3 DVDs. Keep in mind that LOD may vary slightly depending on the mousing surface (pad) it is being used on.

Click Latency

Since mechanical switches are being used for the buttons in most computer mice, debouncing is required in order to avoid unintended double clicks. Debouncing typically adds a delay (along with any potential processing delay), which shall be referred to as click latency. As there is no way to measure said delay directly, it has to be done by comparing it to a control subject, which in this case is the Logitech G203. Click latency has been measured to be roughly +4.3 ms when compared to the SteelSeries Ikari, which is considered as the baseline with 0 ms. Please keep in mind that the measured value is not the absolute click latency. Comparison data comes from this thread as well as my own testing, using qsxcv's program.