I recently built a PC for my brother which is running an AMD A4-3420. This build has no discrete graphics card and I can't seem to install drivers for the built in GPU. I have downloaded the specific Catalyst software, yet there are no graphics options. Does anybody know how I could sort this out as I am stuck in a weird resolution.
That AMD APU is not supported by driver updates anymore since it is considered to be legacy hardware.
These are the drivers from 2015/2016 that AMD has for that APU but none for Windows 10 OS if that is what you have installed: https://www.amd.com/en/support/apu/amd-series-processors/amd-a4-series-apu-for-desktops/a4-3420-rade...
If you need to have a Windows 10 driver then you must let Windows 10 Update download and install the correct Graphics Driver for your APU.
From AMD listing all AMD APUs that are supported by Windows 10: Windows 10 Driver Support for AMD APU Graphics Products