ATI Radeon HD 5870

The ATI Radeon HD 5870 was a high-end graphics card marketed by Advanced Micro Devices (AMD) and released by Apple on August 9, 2010 as a build-to-order option for the 2010 1st-generation Mac Pro. It is based on a GPU chipset originally developed by ATI Technologies (which was acquired by AMD). Supplies of units for separate purchase were constrained until 2012.

Description
The Radeon HD 5870 is based on ATI's high-end Cypress XT workstation graphics chip that was fabricated on the 40 nm process. The GPU clock speed was 850 MHz, which could be boosted to 1.2 GHz, producing up to 2.72 teraflops. It contained 1 GB of GDDR5 video RAM. The card features one dual-link DVI port and two Mini DisplayPorts. It took up the space of a double-wide PCIe 2.0 x16 slot, and required two auxiliary power cables.

Support
The Radeon HD 5870 required a minimum of Mac OS X 10.6.4 (Snow Leopard). Some Mac Pros required a Snow Leopard Graphics Update for improved stability, which was incorporated into Mac OS X 10.6.5 and later. The card was supported through macOS 10.13.6 (High Sierra). However, it does not support Metal, and as a result will not work with macOS Mojave (10.14) or later.

Due to being backwards compatible with older Mac Pros while being less common than its PC counterpart, the Mac version of the Radeon HD 5870 has maintained higher resale values on the aftermarket. However, power users have found that it is possible to flash the cheaper PC version of a Radeon 5000 series GPU card with the firmware from the Mac version.