- Make sure you have installed GT 740m driver from Nvidia http://www.geforce.com/drivers.
- Check if Nvidia Control Panel is on your system tray.
- Download software to monitor your GPU usage/temp and etc such as
// GPU-Z (Gefore GT740m should be named there)
// MSI afterburner (Run this program and simply run a game, check your GPU load, you see if your GPU is working).