howtospark
Training

NVFP4 quantization

FP4 microscalingPlanned

NVIDIA FP4, block 16 with two-level scaling — best perf/accuracy on Blackwell.

On the Spark

The on-device target for Spark/5090: ~1.6× throughput over BF16, ~41% less energy. Our next quant pass for the pruned Hy3.

Relieves
CapacityBandwidthCompute
Targets
Weights · Activations
Format
NVFP4 (E2M1, block 16, two-level scale)
Granularity
Microscaling — block 16 + per-tensor FP32
Lifecycle
PTQ · no gradients
Calibration
Small calibration set
Compression
~4× vs BF16
Quality
98–99% of FP16 with MR-GPTQ calibration
Hardware
Blackwell tensor cores (RTX 5090, B200, GB10) for FP4 throughput; emulated elsewhere
Runtimes
vLLMTensorRT-LLM

A worked Spark recipe for this method hasn't been written yet — it lives here as a reference point in the ontology. It's on the list.