The screen flickering issue occurs only at the bottom of your screen when using AMD-integrated graphics, but there are no issues when using Nvidia graphics. It could be a hardware issue or a problem with the AMD driver. To determine the cause, you can try updating the AMD graphics driver to the latest version. If the issue persists, it's possible that there may be a hardware problem with the AMD-integrated graphics. In such cases, contacting technical support or a computer repair professional would be advisable for further troubleshooting and assistance.
PC Hardware Specialist