Introduction

Quite a few new technologies made their debut at Consumer Electronics Show this year. In the mobile world, Intel’s Core Duo processor made a big splash, while multimedia mavens no doubt were excited to see the first crop of HD-DVD and Blu-Ray players from Sony, Toshiba, Pioneer, and many others on display.

For the PC gamer or hardware enthusiast though, the big news from the show was no doubt the Dell/NVIDIA Quad SLI announcement.

In case you’ve been living under a rock the past month, we’ll provide a quick recap.

Up to now NVIDIA’s SLI technology has been limited to just two GPUs. Two GPUs running in SLI has been just fine and all for gaming at say 1280x1024 or 1600x1200 with 4xAA and 16xAF, but as any gamer with a high-end 21”+ CRT will tell you, 2048x1536 has been the holy grail of gaming for quite some time now. In addition, thanks to rapidly falling LCD prices, an increasing number of gamers are running 24” LCDs like Dell’s highly popular 2405FPW at resolutions as high as 1920x1200, and a new crop of 30” LCDs are flooding the marketplace driving resolution demands even higher. The Dell 3007WFP and Apple Cinema display both run at a native res of 2560x1600. In fact, Dell proudly proclaims that the 3007WFP boasts "over three times the resolution of so-called 'high-def gaming' that comes with an Xbox 360."

To game at resolutions this high with adequate frame rates, two graphics cards just aren’t enough. We’ve also discovered that even NVIDIA’s fastest GeForce 7800 GTX 512MB card begins to chug with NVIDIA’s 16x SLI AA mode. This is where NVIDIA’s Quad SLI technology comes in.

As its name implies, Quad SLI doubles up on the SLI goodness, combining four GPUs to provide double the performance of a conventional SLI setup. NVIDIA also includes a new 32x SLI AA mode that’s unique to Quad SLI.

How it works

Quad SLI is much more complicated than just combining four cards into one system though. In order to make Quad SLI compatible with as wide a range of PCs as possible, NVIDIA combines two GPUs onto one physical card. More specifically, each Quad SLI card combines two PCBs onto one board.

In the case of the Dell demonstration launched at CES, the PCBs for two GeForce 7800 GTX 512MB GPUs were grafted onto one board, requiring one x16 PCI Express graphics slot. You must then combine this card with a second board to enable Quad SLI. The whole setup only requires two x16 PCI Express graphics slots, even though it looks like four cards at first glance.