Sensor

The G.SKILL Ripjaws MX780 uses a high-end laser sensor, the ADNS-A9800 formerly made by Avago (now PixArt). This sensor has its flaws, and unfortunately, it can malfunction quite easily with a fast swipe. The nominal maximum tracking speed and acceleration values are 150 IPS and 30 G. Compared to a modern, high-end optical sensor, like the PMW3360, its values are significantly lower. Since the ADNS-A9500 and A9800, the VCSEL mouse sensor technology hasn't really been moving forward. Most manufacturers choose the better optical sensors because, well, they are better in almost every aspect.

The resolution can be changed from 100–8,200 CPI in increments of 100 CPI. The CPI-changer can cycle through five stages at most, but you can lower the values of these in the software. The polling rate can be set to 125, 250, 500, and 1000 Hz. The default lift-off distance is low enough; it didn't track from one DVD in height (roughly 1.2 mm) at the default setting on a black cloth mouse pad. It can be set to as high as 5 mm if you want, but I would recommend leaving it at the stock value if it works fine.

Paint Test

There isn't any jitter on any of the reasonable CPI steps, or angle snapping and measurable (or audible) sensor lens rattle.

CPI Divergence

CPI accuracy is relatively good; deviations are rather low, only 5% in the negative direction. Please note that this test isn't 100% accurate, but it resembles reality.

Perfect Control Speed

Unfortunately, the perfect control speed was only about 2.6–2.8 m/s depending on the selected CPI value. After reaching this speed, the sensor malfunctions, which has the cursor spin out (you're going to look at the ground in-game, while playing an FPS). It's a pity, but this is the best this sensor can do.

Speed Related Accuracy Variance

This test shows the sensor's accuracy at different speeds. I am doing a fast swipe to the right before I slowly slide the mouse back to its original position. The displacements are quite significant. A laser sensor simply cannot have an SRAV as good as an optical one because of its characteristics.


I did the testing with the MouseTester software, with and without hitting malfunctioning speeds. On the first graph, you can see that the sensor stops tracking at a certain point, and therefore, it doesn't get back to its original position. On the second graph, I did not hit this speed, yet the mouse had a significant amount of positive acceleration during the fast swipe.

Polling Rate

The set polling rates are a bit unstable; there are some random outlier values here and there. I did not notice any negative effects due to these in-game or on the desktop.

Input Lag

I measured +2 ms of input lag on the 2400 and 3600 CPI settings, which then increased to +5 ms on 5000 CPI and went up to +12 ms with the 8200 CPI value. +12 ms is quite significant, but it's generally not recommended to go above 2000–3000 CPI. With this mouse, I would stay at around 1600 at most.

The control subject was once again a Ninox Venator at 800 CPI and 500 Hz.