Rebellions ATOM-Max

The ATOM-Max is the largest card in Rebellions' first-generation line and the part the Korean designer actually ships in volume, sold as RBLN-CA25. It is a full-height full-length dual-slot PCIe card carrying four ATOM neural processors, rated together at 128 TFLOPS of FP16, 512 TOPS of INT8 and 1,024 TOPS of INT4, with 64 GB of GDDR6 at 1,024 GB/s inside a 350 W envelope. Choosing GDDR6 rather than HBM is the whole design argument: Rebellions sells the card on tokens per second per watt against an NVIDIA L40S rather than on peak arithmetic, and the product brief claims roughly four times the L40S' tokens per second per watt on Llama 3.1 70B. Each card carries two dedicated intercard connectors that let up to eight of them talk directly over PCIe Gen5 without going back through the host, in ring, torus or tree topologies, and the compiler splits a model across the chips through what Rebellions calls Rebellions Scalable Design. Eight of these cards make up the ATOM-Max Server at 1,024 TFLOPS and 512 GB. This is not the same silicon as the Rebel100: that part is the four-chiplet HBM3E design announced in 2025, while ATOM is the 2024 GDDR6 generation that preceded it.