Nvidia Corp. formally announced on Monday its highly-anticipated Hybrid SLI technology. The new feature is projected to balance power consumption and computing power requirements of high-end personal computers and improve graphics performance of mainstream machines. Unfortunately, half a year after the first official mentioning, Nvidia does not provide availability timeframe for certain Hybrid SLI features.

Nvidia’s new Hybrid SLI technology will have two modes and that will target different applications: the HybridPower, which will switch off discrete graphics core and use only integrated graphics engine when high performance is not needed, whereas GeForce Boost will make integrated graphics processor (IGP) to assist discrete graphics processing unit (GPU) and boost performance when it is required.

For typical games and 3D applications, GeForce Boost can kick in automatically, resulting in a greatly enhanced consumer experience, as technically Nvidia GeForce Boost is nothing more than an SLI configuration. However, currently there is no driver that can automatically switch between discrete and integrated graphics processors transparently to end-users. While Nvidia promises that transparent transition “will be available in a future software driver” for HybridPower, it does not indicate their availability date. According to some media reports, currently switching to or from discrete GPU requires system restart.

“From the introduction of programmable GPUs to the rapid adoption of our multi-GPU SLI technology, Nvidia has repeatedly pioneered and innovated to solve difficult problems for the industry. We believe Hybrid SLI technology is one of the most important innovations we’ve come up with to date,” said Jen-Hsun Huang, chief executive of Nvidia.

Nvidia plans to release a full lineup of Hybrid SLI-capable graphics and motherboard products in 2008. New Hybrid SLI-capable products include the upcoming Nvidia nForce 780a SLI, nForce 750a SLI, and nForce 730a core-logic sets for AMD microprocessors, which will be released next month, as well as the new GeForce 8200-series chipsets that feature built-in DirectX 10 IGP. Nvidia Hybrid SLI notebooks as well as desktop products designed for Intel microprocessors will be available next quarter.

“Hybrid SLI delivers new multi-GPU technology to a large segment of the PC market, delivering consumers a level of PC graphics performance and power efficiency never before seen,” Mr. Huang added.