Amazon’s founder Jeff Bezos has invested in a chipmaker Tenstorrent – joining Samsung and AFW Partners among others in a monster $693 million Series D round as the company looks to ramp up its RISC-V architecture proposition for AI, in what is a major, arguably contrarian bet.

RISC-V is an open standard, allowing anyone to implement it without the need for licensing fees. Its instruction set architecture (ISA) and extensions are maintained by the non-profit RISC-V Foundation, which has over 4,500 members. These are royalty free and open base building blocks.

The Series D round values Tenstorrent at over $2.6 billion despite it having closed just $150 million in total deals. The company said on December 2 that it would use the influx of capital to “build out open-source AI software stacks, hire developers, expand its global development and design centers, and build systems and clouds for AI developers.”

Tenstorrent’s first chips were made by GlobalFoundries. Its next will be built by TSMC. It has begun designing for 2-nanometer nodes as well. Per Bloomberg, TSMC and Samsung will both start mass production at this cutting edge fabrication scale next year, and “Tenstorrent is in discussions with them and Japan’s Rapidus, which aims for 2nm output in 2027.”

Tenstorrent’s Grayskull and Wormhole “Tensix” processors are built on “baby RISC-V” (an open architecture standard) cores. Its Wormhole processors feature a Network-on-Chip and use Ethernet protocols to network into a multichip mesh for workstations and servers. All of its processors are supported by two open source SDKs for either high-level (TT-Buda) or low-level (TT-Metalium) development said Tenstorrent. 

Customers can already explore its hardware and software via a browser-accessible “Tenstorrent Cloud” with instances featuring up to 2TB memory and up to 96 vCPU available and “storage as needed.”

Tenstorrent is led by AMD and Intel veteran, legendary engineer Jim Keller, who led development of AMD’s K7 and K8 architectures amongst other achievements. Asked on X whether he’d consider the vacant Intel CEO role in the wake of Pat Gelsinger’s resignation, he quipped “maybe as a side hustle. I’m pretty busy.”