Internally, the optical sensor has been upgraded from 1800DPI to 3600DPI. The buttons above and below the scroll wheel adjust the DPI with settings of 400, 800, 1800 and now 3600. The polling rate has also been improved, increasing from 125Hz to 1000Hz, which should eliminate any problems with interface lag.
In hand, the G400 feels very similar to the MX518, differing only in its new matte surface, which feels smoother and less sticker than the glossy MX518. It's still one of the most comfortable mice available, with just the right amount of ergonomic curve. One big complaint of the MX518 was its inability to disable Prediction/Angle Snapping. As a result, tracking was sometimes less perfect. The original batch of G400s shipped with the same problem, however, newer models (PID:LZ13333 and above), have thankfully removed Prediction entirely.
Overall, Logitech have done a great job with the G400, making improvements without changing what made the MX500 lineup work so well. The removal of Prediction on the newer models was a much-needed fix, and has resulted in the best version of one of the longest-lived gaming mice around.
Maximum DPI: 3,600
Number of Buttons: 8
Sensor: Optical
On-board Memory: N/A
Price: S$49