Blackwell
NVIDIA B300 192GB
wins
4
The NVIDIA B300 is the next step in the Blackwell lineup.
Ampere
NVIDIA RTX 3090
wins
1
The RTX 3090 remains a popular budget option for AI workloads with 24GB GDDR6X.
Performance comparison
Visual bars — winner highlighted
NVIDIA B300 192GB
Metric
NVIDIA RTX 3090
FP16 TFLOPS
Bandwidth
VRAM
TDP (lower=better)
TFLOPS/watt
GB/s per watt
Full specification table
| Spec | NVIDIA B300 192GB | NVIDIA RTX 3090 |
|---|---|---|
| Architecture | Blackwell | Ampere |
| VRAM | 192 GB HBM3e | 24 GB GDDR6X |
| VRAM type | HBM3e | GDDR6X |
| Memory bandwidth | 8,000 GB/s | 936 GB/s |
| FP16 TFLOPS | 5,000 TFLOPS | 71 TFLOPS |
| TDP | 1,000 W | 350 W |
| TFLOPS/watt | 5.00 T/W | 0.20 T/W |
| GB/s per watt | 8.00 GB/s/W | 2.67 GB/s/W |
| NVLink | Yes | No |
| Release year | 2025 | 2020 |
Live cloud pricing
On-demand pricing across providers — updated in real time
Power efficiency analysis
TFLOPS/watt and GB/s/watt — critical for data center TCO
NVIDIA B300 192GB
NVIDIA RTX 3090
TFLOPS/watt measures compute efficiency — how much AI throughput you get per watt of power consumed. For data centers with PUE of 1.2–1.5, a 10% improvement in TFLOPS/watt translates directly to lower electricity costs and cooling requirements. GB/s/watt measures memory bandwidth efficiency, which is the binding constraint for memory-bound LLM inference workloads.
When to choose each GPU
Choose NVIDIA B300 192GB for:
- Next-gen LLM training
- Agent inference at scale
- Memory-intensive AI
Weaknesses / Limitations
- Very limited availability — not yet widely deployed on cloud platforms
- 1,000W TDP requires specialized power and cooling
- Premium pricing over B200 with incremental gains
Choose NVIDIA RTX 3090 for:
- Budget fine-tuning
- Small model inference
- Hobbyist AI
Weaknesses / Limitations
- Older Ampere architecture — significantly lower TFLOPS than Ada equivalents
- 350W TDP — high power draw for a 24 GB consumer card
- No ECC memory — not suitable for production reliability requirements
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