Scan-Line Interleave
Scan Line Interleave (SLI) from 3dfx is a method for linking two (or more) video cards or chips together to produce a single output. It is an application of parallel processing for computer graphics, meant to increase the processing power available for graphics. SLI from 3dfx was introduced in 1998 and used in the Voodoo 2 line of graphics accelerators. However also Voodoo Graphics and VSA 100 were SLI-capable.
NVIDIA Corporation reintroduced the name SLI in 2004 (renamed as Scalable Link Interface) and intends for it to be used in modern computer systems based on the PCI Express bus.
Function
 | This article's factual accuracy is disputed. |
3dfx' SLI was the first attempt at combining the power of two video cards. The cards were connected by a small ribbon cable that shared graphics and synchronization information between the cards. Each card rendered alternating horizontal lines of pixels composing a frame.