Question 1

Installer fails or rejects Windows version?

Accepted Answer

The HD 4550 uses legacy ATI Catalyst drivers. Run the installer as administrator in compatibility mode for Windows 7/Vista, or install the INF manually via Device Manager.

Question 2

Device not detected?

Accepted Answer

Reseat the PCIe card, confirm the monitor is connected to the HD 4550’s output—not the motherboard—and check BIOS for PCIe graphics priority. Test another slot if available.

Question 3

Driver version conflicts?

Accepted Answer

Remove existing AMD/ATI drivers with DDU in Safe Mode before installing the matching legacy Catalyst package. Avoid mixing with newer Adrenalin drivers, which do not support the HD 4550.

Sapphire HD 4550 Driver