Founded in 2015, chip design company SiFive recently announced it has completed an oversubscribed funding round raising $4 billion, valuing the company at $3.65 billion. Established by engineers from the University of California, Berkeley, the firm's core technology is based on the open-source RISC-V instruction set architecture. This financing round was led by Atreides Management, with Nvidia also participating as an investor. Other investors include Apollo Global Management, D1 Capital Partners, Point72, T. Rowe Price, among other institutions. Unlike current mainstream CPUs relying on Intel x86 or Arm architectures, SiFive follows a RISC processor route, offering open and neutral chip design licensing. Its business model resembles early-stage Arm, generating revenue through design licensing rather than direct chip sales. Historically, RISC-V has primarily been applied in low-power scenarios such as embedded systems. However, with this funding secured and support from Nvidia, SiFive is accelerating its expansion into the AI data center CPU market. Its chip designs will be compatible with Nvidia's CUDA software ecosystem and support NVLink Fusion server architecture, enabling integration into the "AI factory" built by Nvidia. Industry observers suggest that amid AMD and Intel continuing to challenge Nvidia's GPU dominance, Nvidia's investment in emerging architectural firms like SiFive may aim to build a more diversified AI computing power ecosystem. This fundraising milestone also signals that commercial progress for open-source chip architectures in high-performance computing is gaining momentum.