AM D's strategy at the moment is to focus its design and development efforts on the midrange market and not the top end, using multiple GPUs in a CrossFire configuration to cater to hardcore gamers rather than a single, all-powerful GPU. After seeing how admirably cards based on AMD's 4850 and 4870 GPUs have been performing against their competitors, it's even more interesting to take a look at the 4870 X2. We received a sample from MSI, which follows the reference design without any customizations.

The board is huge and heavy, due to its massive dual-slot cooler. From the underside you can see the two GPUs and a bridge chip in between. The two GPUs run at 750 M Hz, for a total of 1600 stream processors and 2.4 teraflops of graphics processing power between them. The bridging subsystem is an improved version of that found in 3870 X2 cards, with twice the PCle bandwidth as well as a dedicated "sideport" link available between the two GPUs. The other important feature is that each GPU has 1 GB of superfast GDDR5 RAM, for a total of 2 GB soldered onto the board.

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Unfortunately, the mechanics of CrossFire require that both sets of RAM are filled with exactly the same content at all times, meaning the effective total is still only 1 GB although memory bandwidth shoots up to 230 GB/s. The 4870 X2 supports hardware video decoding for smooth HD playback and enhanced antialiasing modes for better visual quality in games at high resolutions. Now for the downsides. Apart from being huge and heavy, this beast also runs very hot and very loud. The fan
was uncomfortably loud when it spun up under a heavy processing load, and temperatures hovered around an average 85 degrees Celsius at the GPU cores.

Even the air exhausted from the back was an astonishing 65 degrees hot! You'll
also need a very capable power supply, since the board can chew up 286 Watts of power with ease. We put the 4870 X2 through our usual battery of benchmarks, and to say that it blew away the competition would be a gross understatement. If) terms of pure performance, the 4070 X2 scored 13,685 points in 3DMark Vantage (Performance mode) as opposed to 10,881 scored by an Nvidia GeForce GTX 280, and 7,513 scored by the regular 4870.

Frame rates in Crysis and Call of Juarez were uniformly higher, even at very high quality settings with up to 4XAA enabled. CrossFire scaling between the two GPUs (as compared to a single 4070) never touched 100 percent, but it was impressively
close to that figure. Keep in mind that all games don't scale so well, and everything depends on continuous driver updates.