AMD offers greater flexibility with its multi-GPU solutions, letting you mix and match any two GPUs based on the same silicon. It was quite natural to expect a Radeon R9 280X to work in tandem with a Radeon HD 7970 GHz Edition from the previous generation, since the two are based on the same "Tahiti" GPU, which is now proven. HardwareCanucks managed to run that combo without a hitch, and log performance results across a bouquet of game tests. The publication also notes that one should be able to similarly pair a Radeon R9 270X with a Radeon HD 7870 GHz Edition (the one based on "Pitcairn," not "Tahiti LE"). Have a Radeon HD 7950? Feel free to add an R9 280X to the mix.