That is strange. Normally on laptops (doesn't matter if it's meant for gaming or office) with an intel integrated graphics GPU and another more powerful GPU, said more powerful GPU would be the default one. However, I might have a solution to this problem. Right click on "My computer" or "This PC" and choose "Manage". It will require administrator privileges. Once the "Computer management" windows opens, look on the right column and choose "Device manager". After that, expand "Display adapters". Under there you should see 2 GPU drivers: one for the Intel HD graphics and one for the Geforce 820M if your computer is working properly. In the event that you only see only one of them, most likely the intel GPU, then right click on "Display adapters" and choose "Scan for hardware changes". If your Geforce card isn't physically broken/damaged, windows should automatically install/update drivers for it. If nothing happens then you are most likely out of luck and that the card has died. In the event that both cards are showing up in Device manager but your programs keep using the less powerful Intel one, you can either somehow force said program to use the Nvidia card or disable the Intel card in device manager. However, note that if the nvidia card is somehow damaged and can't run but is still recognized by windows, your computer might be forced to run said damaged card and the screen might go black, greying out your option to reactivate the Intel card unless you reset the system.