Please refer to the hardware requirements for Visual LANSA Version 14.
VLF Developers should only use the Windows 100% (smaller) font size for development activities. Where VLF end-users may not be using the 100% (smaller) font size the VLF application should be designed, sized and tested at the required larger font sizes. Custom DPI settings are not supported.
The VLF has been designed with the expectation that VLF developers will use a full size screen - at least 1920x1080 pixels.
For deployed applications the system requirements depend on the size and complexity of your application. This may seem to be a less than useful statement, but realistically only you can sensibly size your own resulting application.