SiFive led this week's venture funding activity with a $400 million round that values the semiconductor startup at $3.65 billion, according to Crunchbase data. The funding round underscores investor conviction in the company's bet on RISC-V, an open-source chip instruction set architecture that differs fundamentally from the x86 and ARM processors that dominate current markets. With Nvidia backing and a focus on custom chip design, SiFive is positioning itself as a critical player in an era where companies increasingly demand specialized silicon tailored to their specific workloads rather than relying on general-purpose processors.