AMD (ATI) does not provide a native Windows 10 driver for the HD 4000 series. If you try to install the last official Catalyst driver (v13.9 or v14.4), you’ll likely get an "Installation package failure" or "AMD Catalyst Mobility cannot be installed due to incompatible hardware" error.
Just a heads-up for anyone still running an older card like the ATI Radeon HD 4350, 4550, or similar from the HD 4300/4500 series.
Here’s a draft post for a forum, blog, or tech support thread regarding the driver on Windows 10 . Title: PSA / Guide: ATI Radeon HD 4300 / 4500 Series Driver on Windows 10 (Legacy)