How to Locate and Disconnect Guide
How to Locate and Disconnect GPU Guide
Turn off computer power and unplug it from the electric outlet after 20 seconds.
Open the computer case. A screwdriver might be necessary. Now locate the PCI slot with a large card(GPU) plugged on it. A GPU is usually the largest card plugged on the main board.
Unplug all cables connected to the GPU, unscrew it from the case, and then gently press on the lever of the PCI slot in order to pull the card upwards.
Congratulations. You have just disconnected your GPU.