If you need to know, here is how I fixed it.
First install ViewSonic's "Standard_Monitor_Driver_Signed_Win7_x64"
Go to Device Manager
Select Monitor drop down tab
Select Generic PnP Monitor
Right-Click on Generic PnP Monitor
Select option "Update
Driver Software"
Select "Browse my computer for driver software"
Select "Let me pick from a list of device
drivers on my computer"
Select from the models listed: Generic PnP Monitor
Select option "Have Disk..."
Select "Browse..."
Navigate to where the ViewSonic monitor drivers are stored
Example: C:\ViewSonic
Select monitor driver
Example: VX2450_SERIES
Click "Open"
Click "OK"
Select from the pop up window:
ViewSonic on the left and ViewSonic VX2450 Series on the right
Click "Finish"
Finally, you will receive the message: Windows has successfully updated your driver software.
Notice resolution is now 1680x1050
After successful install of Nvidia drivers for my laptop's "nvidia geforce 9300m gs" current version:
186.19 to new version: 260.99, the max res cannot be set to the following available resolutions:
1920x1200, 1920x1440 or 2048x1536
Enjoy!