RISC-V chip designer SiFive has raised $400 million in an oversubscribed Series G round, valuing the startup at $3.65 billion.

Investors in the Atreides Management-led round included Nvidia, Apollo Global Management, Point72 Turion, and T Rowe Price Investment Management, in addition to existing investors Prosperity7 Ventures and Sutter Hill Ventures.

The funding will help accelerate the company’s RISC-V CPU and AI IP solutions for the data center and expand its global engineering teams to “meet the needs of agentic AI workloads,” SiFive said in a statement.

SiFive chairman and CEO Patrick Little added: “Hyperscale customers have made it very clear that it is time to accelerate the availability of open standard alternatives for the data center.

"Their consistent ask is for customizable CPU solutions in IP form, that will enable them to meaningfully differentiate their data center compute solutions."

Founded in California in 2015, SiFive is a fabless chip company that designs chips based on RISC-V, the open architecture that is increasingly seen as a useful alternative to the dominant x86 and Arm ecosystems.

In July 2024, it launched SiFive Performance P870-D, a data center-focused processor for AI workloads. In September of that same year, the company unveiled its XM Series of AI accelerators for high-performance workloads across Edge, IoT, and data center use cases.

In January, the company announced it would be integrating Nvidia’s NVLink Fusion interconnect technology with its future designs.