The Radeon HD 5770 is a huge step up from the GeForce GT 120 that previously came standard in the Mac Pro. Don't get too excited, the multi-GPU route is explicitly for more displays there's no concept of CrossFire under OS X at this point. For an extra $200 you can get a Radeon HD 5870 with 1GB of GDDR5, and for an extra $250 you can have two 5770s instead of one. Clocked and spec'd identically to the PC version, this is the graphics card you get in all three standard models. The GPU of choice in the Mac Pro is the Radeon HD 5770 equipped with 1GB of GDDR5. To be fair though, Apple has alternated between NVIDIA and AMD for graphics every year for the past four years. With the exception of the Mac mini, every single Apple desktop uses an Intel CPU, an Intel chipset and an AMD GPU. In one fell swoop Apple pulled NVIDIA out of almost all of its desktop products.
