The Architecture Bet: Efficiency Over Frontier Scale
Most models in the Nemotron 3.5 family lean on the same efficiency logic: a mixture-of-experts design where only a fraction of total parameters activate per token - confirmed for Super VL, Lightning, and Bolt 74B-A9B, though NVIDIA has not published an active-parameter breakdown for Bolt E4B or Ultra. Super VL carries 120 billion total parameters but activates just 12-13 billion per token [1], trained on roughly 26 trillion tokens plus 3.8 million reinforcement-learning samples [12]. That same efficiency ratio runs down the stack - Lightning ships as 30B total with 3B active, and Bolt 74B-A9B keeps 74B total parameters but only 9B active, squeezed further by native 2-bit quantization so the whole thing fits in 24GB of memory. The training recipe is where the post-training story gets specific: NVIDIA reports fine-tuning lifts of 9-44% on narrow tasks, for example moving security-attack resilience from 35% to 76% accuracy [1]. Super VL's hybrid Mamba-2/attention layers are also why the model does not simply drop into any inference stack - vLLM 0.27.1 or newer is a hard requirement, since older serving engines don't have the Mamba-2 kernels compiled in [2], a detail several outlets flagged as the most likely practical snag for teams trying to self-host on day one.


