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Pyyan / Compare / B300 Blackwell Ultra vs MI400 vs H100

B300 Blackwell Ultra vs MI400 vs H100

3 of 5

GPU & AI Chips · verified 13 Aug 2026

×B300 Blackwell UltraNVIDIAcurrent
×MI400AMDcurrent
×H100NVIDIAcurrent
2 slots left
SpecificationB300 Blackwell UltraMI400H100
Summary15 PFLOPS dense FP4.Double NVIDIA's memory capacity.The workhorse of the previous generation.
Memory288GB HBM3e432GB HBM480GB HBM3
Bandwidth8 TB/s19.6 TB/s—
Price~$40–50K (verify)—$25–40K
VendorNVIDIAAMDNVIDIA
CategoryGPU & AI ChipsGPU & AI ChipsGPU & AI Chips
OfficialNVIDIA ↗AMD ↗NVIDIA ↗

Highlighted rows are where these differ.

B300 Blackwell Ultra

  • 8 TB/s memory bandwidth
  • Per-GPU pricing widely misquoted — one source cites rack pricing

Best for frontier training.

Full spec sheet →

MI400

  • 19.6 TB/s bandwidth
  • 40 PFLOPS FP4
  • $7.2B in commitments

Best for large-model inference.

Full spec sheet →

H100

The workhorse of the previous generation.

Best for value.

Full spec sheet →