The idea behind combining multiple graphics processors to increase performance is nothing new. While you might be familiar with recent SLI and Crossfire solutions from modern-day video card manufacturers nVidia and AMD/ATI, the birth of multi-GPU 3D gaming can be traced back more than ten years ago to a company called 3dfx and their Voodoo2 graphics chipset.

Through their Scan Line Interleave technology, 3dfx allowed you to combine two Voodoo2 PCI cards together, theoretically doubling 3D gaming performance. Although 3dfx was subsequently bought out by rival manufacturer nVidia, multi-GPU technology practically disappeared for a period of around four years, until being resurrected again by nVidia in 2004, this time to be known as Scalable Link Interface. AMD also developed their own solution, named Crossfire.

Fast forward another four years and we find nVidia and AMD/ATI again competing on a new graphics front, combining the integrated motherboard graphics chipset commonly found in low-cost mainstream computer systems with that of a more traditional separate discrete graphics card. This hybrid mix of technologies has been appropriately dubbed Hybrid Graphics by AMD/ATI and Hybrid SLI by nVidia.

You can read the entire article at OCIA.