Hybrid SLI samples are expected to be shipped out in the second half of April, which means the final products will end up at retail sheleves by late May.
The basics of Hybrid SLI aren't very difficult to understand. The term itself envelopes two different NVIDIA technologies, GeForce Boost and HybridPower. GeForce Boost allows for a single discrete NVIDIA graphics card to be paired with an NVIDIA motherboard's integrated graphics. HybridPower, on the other hand, dynamically throttles the discrete graphics adapter as needed.
The delay notification reads, "We are still experiencing delays in getting the kits sent as the product is experiencing delays, drivers are being fine-tuned and sales tools are being finalized."
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Cards that currently support Hybrid SLI include the GeForce 8500 GT as well as the GeForce 8400 GS. The chipsets that support Hybrid SLI include the NVIDIA nForce 720a and the nForce 730a.