Mar 24, 2025

Nvidia embraces optical tech – but not for GPUs (yet) The chips will be three and a half times more energy-efficient than their predecessors The big picture: Nvidia's approach to co-packaged optics is a nuanced reflection of the technology's current limitations and future potential. By focusing on specialized applications with less demanding reliability requirements, Nvidia is positioning itself to lead the development of optical technologies for networking and data center applications while continuing to rely on traditional copper connections for its high-performance GPUs. Nvidia CEO Jensen Huang recently addressed the reliability of co-packaged optics, a technology that uses laser light to transmit data between chips, and its potential use in the company's flagship GPUs. During the company's annual developer conference, Huang noted that while co-packaged optics offer superior energy efficiency and speed compared to traditional copper connections, they are not yet reliable enough for widespread use in Nvidia's GPUs. This reliability gap is significant, with copper connections being "orders of magnitude" more reliable than current co-packaged optical connections, making them the preferred choice for Nvidia's GPUs, Huang told a group of journalists after his keynote speech. However, Nvidia is exploring using co-packaged optical technology in more specialized applications. Huang said that the company plans to integrate the technology into two new networking chips designed for switches on top of its servers. These chips, set to be released later this year and in 2026, will be three and a half times more energy-efficient than their predecessors. This marks a significant step forward in advancing the technology, albeit in a more niche application where the reliability requirements might be less stringent than those for high-performance GPUs. Nvidia has also made significant strides in silicon photonics, with the introduction of its Quantum-X and Spectrum-X networking switches last week. These switches integrate optical communications into electronic circuits at a massive scale, enabling AI factories to connect millions of GPUs across sites while reducing energy consumption and operational costs. Nvidia claims these optics innovations use 4x fewer lasers to deliver 3.5x more power efficiency, 63x greater signal integrity, 10x better network resiliency at scale, and 1.3x faster deployment than traditional methods. // Related Stories Huang highlighted the importance of the new networking switches, stating, "AI factories are a new class of data centers with extreme scale, and networking infrastructure must be reinvented to keep pace." By integrating silicon photonics into switches, Nvidia is pushing the boundaries of what is possible in hyperscale and enterprise networks, paving the way for "million-GPU AI factories," the CEO said. The industry's shift towards optical technology is driven by the need to address the increasing power consumption and heat generation associated with traditional copper connections. As AI computing demands grow, companies like Nvidia and startups such as Ayar Labs are exploring ways to make co-packaged optics more reliable and cost-effective. Mark Wade, CEO of Ayar Labs, told Reuters that while transitioning to widespread use of co-packaged optics may not occur until 2028 or beyond, optics is essential for building larger servers without being constrained by copper's limitations. "Just look at the power consumption going up and up on racks with electrical connections," Wade said. "Optics is the only technology that gets you off of that train."