With the release of the Voodoo2 in the beginning of 1998, an innovation of 3dfx, SLI technology (Scan Line Interleave), allowed the possibility to use two graphic cards in a single computer. This new configuration had two main advantages of increased performance and the possible use of 1024 x 768 instead of 800 x 600 with a single card. At that time, each card managed every other line, allowing 3dfx an unmatched raw performance better than the NVIDIA Riva TNT for those able to invest $500 in a 3D graphic card.
Then came ATI with the use of two graphic chips in parallel with the Fury MAXX in late 1999/ early 2000. This graphic card included two Rage 128 Pro, and was designed to compete with the NVIDIA GeForce 256 until the arrival of the first Radeon. ATI’s technology was called AFR (Alternate Frame Rendering) where each chip processed one image after another. Less efficient than a GeForce DDR this graphic card was a failure.
After 3dfx and ATI, it’s now up to NVIDIA to release a new SLI product for standard users, a product that is in widespread use in computers with military simulations games, for example.
The first step-the motherboard and chipset
If NVIDIA has the right to use the SLI name after buying 3dfx, the GeForce manufacturer has decided to change a few details. SLI isn’t Scan Line Interleave anymore, but rather Scalable Link Interface.
The first step for the new SLI generation is the need for a motherboard equipped with two PCI Express slots. PCI express is controlled by the chipset, and the good thing is that NVIDIA is also the chipset manufacturer. This is the reason they have developed a SLI version capable of using the 20 lanes in a flexible way (see
our article on the subject).
You may have noticed that the ASUSTeK A8N-SLI includes 4 PCI Express slots. It’s actually one x16 slot, two x1 slots and another x16 slot. For signal branching, a configuration card located between the two PCI Express x16 slots makes it possible to change between the two.
- Single Graphic Card: 1st slot branched in x16 (4 GB /s), second in x1 (250 MB /s)
- Dual Graphic Card: 2 slots branched in x8 (2 Go /s)
With two graphic cards it’s possible to use only one of the two PCI Express x1 slots. ASUSTeK is one of the first manufacturers to release an nForce 4 SLI motherboard. There are two versions:
- A8N-SLI, $179
- A8N-SLI Deluxe, $199
Already in mass production, these motherboards should be available in early December. The Deluxe version adds a PCI Silicon Image 3114R chip to manage 4 SATA in RAID ports in addition to the 4 ports managed by the chipset and a PCI Marvell Gigabit Ethernet chip to have a second Gigabit network port.
Both motherboards include FireWire (with TI chip), audio management (with a Realtek ALC850 chip) and, of course, the nForce4 SLI function.
Recommended prices lead us to believe that the nForce4 Ultra will have less of an impact compared to the nForce4 SLI. It should be possible to find a basic A8N-SLI starting from $160.
The SLI connector comes with the nForce4 SLI motherboard, used to connect two graphic cards compatible with this function.
