VPU's to accelerate ZK Proving were announced by Polygon and Fabric in September 2024.

Here's an interesting video where Paul Barron talks about VPUs.
https://www.youtube.com/watch?v=w4U7GYSY8SU

INTRODUCING THE VPU

https://www.fabriccryptography.com/

Fabric Teams Up with Polygon Labs to Introduce Revolutionary Hardware: Verifiable Processing Units (VPUs) for ZK

Custom chips will change the ZK game by removing persistent barriers to maximizing performance

Fabric is building a Processor for Web3, optimized for ZK

Let’s take a moment to imagine the ideal hardware to support Polygon ZK technology. It would need to be high-performance. It would need to support general-purpose cryptography. It would need to be easily programmable. And it would need to be scalable—that is, mass producible and affordable.

So what can check all these requirements? An ASIC, like those developed for Bitcoin? No. ZK proof systems change too fast for something like a fixed function ASIC to keep up.

The best solution is a custom processor, optimized for ZK cryptography.

Fabric’s VPU (Verifiable Processing Unit) will support dozens of cryptographic primitives, from the generalized Merkle tree to Plonk and beyond. It will also support more big-integer operations than a typical GPU–900%, to be exact.

As the world’s first massively parallel, general-purpose processors for cryptography, Fabric’s VPUs will also offer vastly superior performance compared to widely used general-purpose CPUs or GPUs. Each VPU card features 3 FC1000 chips.The FC1000 chip is a complete system-on-chip dedicated to accelerating proof systems end-to-end. It uses an on-chip CPU (RISC-V), exceptional memory bandwidth, and unprecedented cryptographic compute (40 custom tiles per chip, and 120 tiles per card). Workloads are also highly performant and parallelizable, from the chip to the server level, due to Fabric’s full compiler and software stack.

More at the link below:

https://polygon.technology/blog/fabric-teams-up-with-polygon-labs-to-introduce-revolutionary-hardware-verifiable-processing-units-vpus-for-zk