(released in June 2008) can be tricky because it is now a . AMD no longer provides active updates for this card, meaning the latest available drivers are several years old and were originally designed for older operating systems. Official Driver Downloads

The latest stable version is Catalyst 13.9 (released in October 2013).

Support is available for both 32-bit and 64-bit versions of XP for users maintaining retro gaming builds. Installing on Windows 10 and 11 There are no dedicated Windows 10 or 11 drivers for the Radeon HD 4870

You can try installing the Windows 8 (64-bit) Catalyst 13.1 driver. Right-click the installer, select Properties , go to the Compatibility tab, and set it to run for Windows 8.

The Radeon HD 4870 was a performance-segment graphics card by ATI, launched on June 25th, 2008. TechPowerUp ATI Radeon HD 4870 512MB Review - Phoronix

For the most stable experience, you should download drivers directly from the ATI Radeon HD 4870 support page on AMD's website.