NVIDIA 3-Way SLI Performance Preview

It’s been nearly two years since NVIDIA first announced their Quad SLI technology at CES 2006. NVIDIA learned a lot of hard lessons bringing Quad SLI to market. As you probably know, initial GeForce 7900 GX2 Quad SLI boards were massive, measuring in just over one foot in length. This made boards difficult to fit in many cases and ultimately restricted the 7900 GX2 boards to system builders only. We took a look at the technology in a system sent to us by ABS and found that while Quad SLI worked, the platform was buggy (we ran into numerous crashes and BSODs in Windows) and that Quad SLI performance wasn’t quite up to the level that was expected when the technology was first announced, even at ultra high-resolutions such as 2560x1600.

Ultimately there were only a handful of cases were the technology really showed its full potential.

NVIDIA eventually ironed these issues out with the debut of their second generation Quad SLI card, the GeForce 7950 GX2, but these cards were extremely expensive and due to limitations within DirectX 9, the 7950 GX2 didn’t always offer true 4-way AFR scaling in Direct3D games. In order for the GeForce 7950 GX2 Quad SLI to truly shine, you had to crank up the AA to 8x. Here the GeForce 7950 GX2 Quad SLI platform really began to pull away from more conventional SLI setups like the GeForce 7900 GTX SLI.

When NVIDIA introduced the GeForce 8800 GTX last year, they were quick to point out the GPU’s ability to scale to additional cards. At the time, they were mum on what their specific plans were, but now we can finally reveal what that second SLI header on the GTX and Ultra is for: 3-Way SLI!

“Who needs 3-Way SLI anyway?”

This is probably the first question someone who’s not intimately familiar with PC gaming would ask. “Exactly who needs three graphics cards anyway?” Obviously, 3-Way SLI isn’t intended for the casual gamer who occasionally plays a round of Counter-Strike: Source or World in Warcraft. This is for the guy who wants the best performance possible with the best image quality. If you lust after the graphics you see on the back of the game box – the high polygon characters with high-res textures and jaggie-free, 100% smooth edges – but also want blazing performance, 3-Way SLI is for you. As any gamer who’s picked up a cutting-edge title like Crysis will tell you, even with dual GeForce 8800 GTX graphics cards running in SLI, the frame rate can drop pretty quickly with the game set to its maximum settings.

Gamers with 30” monitors would benefit from 3-Way SLI as well. Going from two to three cards should allow you to game at 2560x1600 with even higher frame rates than a conventional 2-Way SLI setup would provide.

And by using standard off-the-shelf components like the nForce 680i and GeForce 8800 GTX/Ultra, 3-Way SLI should be more user-friendly than Quad SLI was. 3-Way SLI doesn’t run into the same DX9 limitations as Quad SLI, and NVIDIA has had a year to tweak the technology so it’s compatible with more games. All this should make 3-Way SLI more user friendly than Quad SLI ever was. That’s the theory at least. Today we’re here to find out how effective NVIDIA’s 3-Way SLI solution is in the real world.