Satan exerts his evil control over your touchpad through improper grounding (see
http://rog.asus.com/forum/showthread.php?9639-G74SX-touchpad&). A metallic tape is used to ground the touchpad and due to poor manufacturing, was not properly applied to effectively ground the device.
@Brodyboy provided a good discussion on this issue in
http://rog.asus.com/forum/showthread.php?883-Troubleshooting-ASUS-G73-Touchpad-Problems/page41. This problem was first encountered with G73 touchpads and has been mostly eradicated in the recent G75/G55/G46 series.
Note that the key players in the threads on this issue can no longer be contacted here. @Chastity, once known as the "ASUS erratic touchpad expert" hangs out at the Notebook Review Forum these days. @Brodyboy hasn't been seen on this forum since he fell into the abyss battling with the Balrog that Satan sent after him for exposing his demonic touchpad possessions.
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT