Just when we thought we'd seen just about all you could from SLI, with the craziness that is 3-way SLI nVidia goes and surprises us again with Hybrid SLI. In fact, I'd go so far as to say this is actually the most interesting implementation I've yet seen of a multi-GPU setup. The two technologies making up Hybrid SLI are called GeForce Boost and Hybrid Power and both work together to provide a very nice graphics solution.
The premise of GeForce boost is simple, think SLI with two of the same graphics cards and then remove one of these and replace it with integrated graphics on the motherboard. What this means is that if you have an nVidia nForce 780 chipset on your motherboard, which packs some form of onboard graphics you can add a dedicated graphics card (currently the choice is a GeForce 8400 or 8500 but all future cards will work) and instead of simply getting the power of the new card, you'll also get the extra juice from the integrated graphics. nVidia is claiming up to a 40 per cent boost in 3DMark06, which is a wonderfully unhelpful figure considering how little relation to the real world that benchmark has. In the real world though, it can probably be considered as the difference between playing Counter-Strike: Sideshow and Counter-Strike: Source on the average notebook and that isn't to be sniffed at.
That's Geforce Boost then, but what of Hybrid Power? Well, let us return to our hypothetical system which has both an integrated graphics chip and a dedicated card and let us assume that the user is listening to iTunes, typing a word document or browsing TrustedReviews or, in other words, not using the graphics card's power at all. Normally that GPU is sitting there slowly increasing your electricity bill and global warming. Hybrid Power enables the system to turn off the dedicated card and use the integrated graphics in these situations. For the curious, it is worth mentioning that this is a Vista-only feature, because of driver limitations I'm really not going to try and explain, mainly because I don't have a PhD in software engineering.
Currently, only AMD nForce 7-series boards are compatible with the new features, which is a nicely ironic twist, and you'll need an GeForce 8200m integrated chip to use Hybrid SLI but going forwards nVidia expects every product in its range to be compatible. Bearing in mind that with Hybrid SLI nVidia is saving graphics power and providing more of it in one fell swoop, please feel free to insert your own joke about the green team being green by name and nature here.