It's important to install the
correct driver. Otherwise the touchpad will not perform correctly. A Synaptics driver installed to a Sentelic toucpad will make it appear to be a Synaptics touchpad in Device Manager.
I recommend you uninstall your current touchpad driver from "Control Panel - Uninstall a program, REBOOT, and Windows will install its Plug-n-Play touchpad driver. THEN go into Device Manager, right-click on the touchpad device and choose "Properties" from the popup menu. Select the "Details" tab.
When you choose "Hardware ids", what is displayed in the "Value" section. I believe if it has "STLC" in the value, it will confirm you have a Sentelic touchpad. If the Hardware ID is different, you have a Synaptics touchpad.
Once you know which; install the correct driver from the links @Dixon provided. I recommend 9.1.7.7 if you have a Sentelic touchpad.
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT