The limiting factor there was power draw. The card’s sheer length and price tag were both plenty extreme, but its 725MHz default clock speed gave it performance closer to a pair of Radeon HD 5850s than to a pair of higher-end 5870s. The Radeon HD 5970 was odd in that it wasn’t the absolute pinnacle of extremeness that one would expect out of this class of product. Instead, recent flagship Radeons have been based on pairs of mid-sized chips. The company has been carefully refining its dual-GPU products over the past few years, ever since it decided to stop producing as-big-as-you-can-make-them GPUs. Much of the credit for that fact goes to AMD. Nevertheless, these odd creations are here to stay. Yet dual-GPU cards don’t garner loads of attention, for a host of reasons: they’re subject to the same performance and compatibility pitfalls as any multi-GPU configuration, they tend to have rather extreme power and cooling needs, and they’re usually really freaking expensive, to name a few. For over a year now, for instance, the Radeon HD 5970 has held that title. Technically, one of them is probably the fastest video card on the planet at any given time. Dual-GPU graphics cards have always been kind of strange.
