PyyanThe AI Index

Pyyan / Compare / MI400 vs B300 Blackwell Ultra vs H100

MI400 vs B300 Blackwell Ultra vs H100

3 of 5

GPU & AI Chips · verified 13 Aug 2026

×MI400AMDcurrent
×B300 Blackwell UltraNVIDIAcurrent
×H100NVIDIAcurrent
2 slots left
SpecificationMI400B300 Blackwell UltraH100
SummaryDouble NVIDIA's memory capacity.15 PFLOPS dense FP4.The workhorse of the previous generation.
Memory432GB HBM4288GB HBM3e80GB HBM3
Bandwidth19.6 TB/s8 TB/s—
Price—~$40–50K (verify)$25–40K
VendorAMDNVIDIANVIDIA
CategoryGPU & AI ChipsGPU & AI ChipsGPU & AI Chips
OfficialAMD ↗NVIDIA ↗NVIDIA ↗

Highlighted rows are where these differ.

MI400

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

Best for large-model inference.

Full spec sheet →

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 →

H100

The workhorse of the previous generation.

Best for value.

Full spec sheet →