What is SLI?

SLI or Scalable Link Interface is a technology that lets you take two identical NVidia based graphics cards *that support SLI* and a motherboard *that supports SLI* to achieve a very high level of video performance. SLI works by splitting the rendering of the screen between the two cards- one card renders half, the other card renders the other half. This technique is extremely effective. For instance two 6600GT cards in SLI can do vastly better than a 6800GT or X800 card even though the price is lower for two 6600GT Cards. The downside to this is that SLI is still new and is limited to systems based on AMD 64 / AMD FX Socket 939 processors.