Nvidia details Hybrid SLI at CES
As Ars Technica detail, Hybrid SLI will use two technologies: GeForce Boost and HybridPower. HybridPower will allow on-the-fly switching, depending on how demanding the task, between the on-board graphics, and the more powerful graphics card(s) – drastically reducing power bills.
The upcoming NVIDIA 780a SLI, 750a SLI, and uATX GeForce 8200 chipsets will all be compatible with Hybrid SLI. All future NVIDIA video cards will support Hybrid SLI as well, but two current models?the 8400GS and 8500GT?will support GeForce Boost when paired with an appropriate motherboard. As for availability, the new boards and chipsets will be available in the first quarter of 2008 for AMD CPUs, with Intel availability to follow in the second quarter.
On the other hand, GeForce Boost welds the integrated GPU with the discrete GPU, resulting in improved performance. When using GeForce Boost, the monitor is connected to the motherboard’s video outputs, meaning the discrete GPU’s frame buffer must first pass through the integrated GPU. Nvidia suggests that on PCIe 2.0, there is plenty of bandwidth for this.
The real-world performance gain from using GeForce Boost is unknown. NVIDIA claims a 40 percent improvement in 3DMark 2006 when GeForce Boost is enabled, but gives no information on which integrated and discrete solutions were combined to achieve that number. It’s hard to tell how the system’s increased 3DMark score correlates to other games, but NVIDIA was kind enough to include the additional bar graph quantitatively demonstrating the performance benefits of GeForce Boost.
Nvidia notes that GeForce Boost is designed for entry-level systems with similar performing discrete and integrated GPU’s. Running the setup on a mid or high-end setup with a poor performing IGP will likely “decrease performance”.