NVIDIA SLI (Scalable Link Interface) is a technology that allows multiple NVIDIA graphics cards to work together in a single computer system. This setup enhances graphics performance by distributing the workload across the connected cards, resulting in smoother gameplay and improved frame rates in demanding applications. To use NVIDIA SLI, users need a compatible motherboard and at least two NVIDIA graphics cards that support the technology. The cards communicate through a high-speed connection, enabling them to share rendering tasks. This can significantly boost performance in video games and graphic-intensive software, making it a popular choice among gamers and professionals.