Nvidia Corp., the No. 1 supplier of discrete graphics processing units (GPUs), on Tuesday once again unveiled its Hybrid SLI technology designed to boost performance of low-end graphics sub-systems as well as save energy in cases of high-end graphics cards. This is the third time in the last twelve months when Nvidia intros the technology, though, hopefully it will now be available commercially.

“Hybrid SLI will give consumers the extra GPU performance they need for the increasing numbers of visual PC applications such as today’s PC games. And it will give gamers and PC enthusiasts the quiet and power savings they demand. Hybrid SLI components could very well pay for themselves over the life of the PC,” said Drew Henry, general manager of platform business at Nvidia.

Nvidia Hybrid SLI technology – that requires Nvidia GeForce graphics card and Nvidia nForce-based mainboard – has two modes: the HybridPower, which switches off discrete graphics core and uses only integrated graphics engine when high performance is not needed; the GeForce Boost mode makes integrated graphics processor (IGP) to assist entry-level discrete graphics processing unit (GPU) and boost performance when it is required.

The Hybrid SLI-enabled desktop PC motherboards are designed to create a PC with GeForce GPUs and AMD Phenom processors. There are currently eight chipset models that support HybridPower and GeForce Boost, including nForce 780a SLI, nForce 750a SLI, nForce 730a, nForce 720a, GeForce 8300, GeForce 8200, and GeForce 8100. Besides, there are two graphics cards supporting HybridPower – GeForce 9800 GX2 and GeForce 9800 GTX – and two GeForce Boost-capable graphics cards, including GeForce 8400 GS and GeForce 8500 GT GPUs.

Nvidia’s Hybrid SLI technology is not free of certain limitations that may impact popularity of technology. According to media reports, the first implementation of Hybrid SLI technology not only does not support multi-monitor output capability, but also does not feature dual-link DVI output, which means that such a system cannot support 30” high-end displays with resolution of 2560x1600.

Nvidia formally disclosed information about Hybrid SLI technology in late June, 2007, and promised that the first systems to sport the feature would be available in later 2007. The company officially unveiled the technology in January, 2008, promising to make appropriate hardware available in 2008. In early May, 2008, the company stated that its Hybrid SLI supporting products were available.

Hybrid SLI-enabled PC motherboards for Intel processors and Hybrid SLI-enabled notebooks will be available in Q3 of 2008, Nvidia said.