The R680 designates, in reality, the Radeon HD 3870 X2, which is based on two RV670 GPUs. As we've seen, the history of multi GPU cards is pretty diverse and if this HD 3870 X2 represents a departure from the concepts behind the Voodoo 5500 (the VSA 100 having been conceived to be grouped at least in twos, from the beginning, to produce an efficient card), its goal is reminiscent of the Rage Fury MAXX in 1999; to offer a product to place in front of the high end models of its Californian competitor.

AMD has decided to integrate two RV670s on the same PCB (for more information on the chip refer to the Radeon HD 3850 and 3870 review). This is, without a doubt, to allow the installation of a imposing cooling system and to facilitate the interconnections between the two graphical sub systems. The result is a monster of 26.7 cm in length (longer than the width of a motherboard). This value is identical to what we have on a GeForce 8800 GTX and Ultra, which holds only one chip.

System Configuration Used:

Test Setup
• Power Supply: Coolermaster RealPower Pro 850W
• Motherboard: Asus P5E3 Deluxe (X38)
• Processor: Intel Core 2 Extreme QX6850 (Quad-core 3 GHz)
• Video: ATI Radeon HD3870X2, ATI Radeon HD3870, ATI Radeon HD2900XT, NVIDIA GeForce 8800GTS, NVIDIA GeForce 8800 Ultra, ATI Radeon HD3870 Crossfire
• Memory: Crucial 2 x 1 GB DDR3 1333 MHz 9-9-9
  
  Software Configuration
• Video Driver: ATI Catalyst 8.1 beta (8-451-2-080108a), NVIDIA ForceWare 169.28 beta

• Test Drive Unlimited
• Supreme Commander
• Age of Empires 3
• Oblivion
• STALKER
• World in Conflict
• Unreal Tournament 3
• Crysis
• Call of Duty 4

http://neowin.net/news/main/08/01/28/ati-radeon-hd-3870-x2---fastest-yet