Plzz help me i have B450 motherboard gigabyte processor ryzen 5 2400g Ram 8 gb Corsair os window 8.1 when i'm installing AMD graphics driver by cd my system crash and when i download new drive AMD site its not install plzz help me.... what i do
Do you have right driver ? They are not same for integrated and for dedicated graphics. Check here https://www.amd.com/en/support for proper driver, Choose "Processor with graphics".
You should also upgrade to W10, Windows 8/8.1 drivers are scarce nowadays for newer GPUs.