B300 SXM6 vs MI325X

Blackwell UltravsCDNA 3Updated 35 days ago

B300 emerges as the superior choice for prevalent AI training and inference use cases. Its 2250 TFLOPS FP16, 4500 TFLOPS FP8, 288 GB VRAM, and 12000 GB/s bandwidth outperform MI325X equivalents of 1307 TFLOPS FP16, 2614 TFLOPS FP8, 256 GB VRAM, and 6000 GB/s, enabling larger models and higher throughput despite higher 1200W TDP.

B300 SXM6 from $7.39/hr

Specifications Compared

SpecB300MI325X
TDP1200W750W
VRAM288 GB256 GB
Memory TypeHBM3eHBM3e
ArchitectureBlackwell UltraCDNA 3
Form FactorsSXMOAM
InterconnectNVSwitch, NVLinkInfinity Fabric
FP8 Performance4,500 TFLOPS2,614 TFLOPS
FP16 Performance2,250 TFLOPS1,307 TFLOPS
FP32 Performance90 TFLOPS1307 TFLOPS
FP64 Performance45 TFLOPS40.9 TFLOPS
INT8 Performance4,500 TOPS2,614 TOPS
Memory Bandwidth12,000 GB/s6,000 GB/s

Performance Analysis

B300's FP16 performance reaches 2250 TFLOPS, doubling MI325X's 1307 TFLOPS and enabling faster AI training where half-precision arithmetic prevails. The FP32 gap is pronounced: MI325X delivers 1307 TFLOPS while B300 manages only 90 TFLOPS, favoring MI325X for precision-dependent simulations and certain inference pipelines. FP8 capabilities follow suit, with B300 at 4500 TFLOPS versus 2614 TFLOPS on MI325X, benefiting quantized inference on B300. Memory bandwidth of 12000 GB/s on B300 supports larger batch sizes in training compared to 6000 GB/s on MI325X, reducing data loading bottlenecks for massive datasets. The 288 GB VRAM on B300 accommodates larger models without offloading, unlike MI325X's 256 GB limit, which impacts long-context inference efficiency.

Live Cloud Pricing

Real-time prices from 25+ providers. Updated every 60 seconds.

B300 SXM6

ProviderGPU ModelVRAMHost SpecsRegionPriceStatusAction
RunPod
RunPod
NVIDIA B300 SXM6
262GB VRAM
$7.39/GPU/hr
Scaleway
Scaleway
8×NVIDIA B300 SXM6
262GB VRAM
$8.73/GPU/hr
$69.84/hr total (8×)
Available

Compare real-time pricing across 25+ providers

When to Choose the B300 SXM6

B300 suits memory-intensive workloads like large-scale LLM training. Its 288 GB VRAM and 12000 GB/s bandwidth handle models exceeding 256 GB contexts without performance degradation. FP16 throughput of 2250 TFLOPS accelerates iterations in deep learning pipelines. For inference on quantized models, 4500 TFLOPS FP8 provides superior speed. NVLink interconnect enhances multi-GPU scaling in SXM form factor.

When to Choose the MI325X

MI325X fits power-sensitive deployments with 750W TDP versus B300's 1200W. Balanced FP16 and FP32 at 1307 TFLOPS each excel in hybrid precision tasks such as scientific simulations. Infinity Fabric interconnect supports dense OAM configurations. Lower bandwidth of 6000 GB/s suffices for workloads not bottlenecked by memory access.

Use Cases

LLM Training
B300 SXM6

B300's 2250 TFLOPS FP16 and 12000 GB/s bandwidth support massive batch sizes and faster convergence on large models. MI325X trails with 1307 TFLOPS FP16 and half the bandwidth.

LLM Inference
B300 SXM6

B300's 4500 TFLOPS FP8 and 288 GB VRAM enable low-latency serving of long-context models. MI325X's 2614 TFLOPS FP8 and 256 GB VRAM limit scale.

Fine-tuning
Either

B300 accelerates with higher FP16; MI325X suffices for FP32-heavy fine-tuning at 1307 TFLOPS. Choice depends on precision needs and power budget.

Stable Diffusion
B300 SXM6

B300's 12000 GB/s bandwidth and 288 GB VRAM boost image generation throughput. Superior FP16 performance doubles MI325X's capacity.

Scientific Computing
MI325X

MI325X's 1307 TFLOPS FP32 vastly outpaces B300's 90 TFLOPS for simulations. Lower 750W TDP aids dense clusters.

Frequently Asked Questions

Which GPU has more VRAM?

B300 offers 288 GB HBM3e VRAM compared to MI325X's 256 GB HBM3e. This edge allows B300 to load larger models directly.

How do memory bandwidths compare?

B300 provides 12000 GB/s, twice MI325X's 6000 GB/s. Higher bandwidth on B300 reduces latency in data-heavy AI tasks.

What are the FP16 performance differences?

B300 achieves 2250 TFLOPS FP16 versus MI325X's 1307 TFLOPS. B300 excels in training workloads using half-precision.

Which has higher power consumption?

B300 requires 1200W TDP, while MI325X uses 750W. MI325X suits power-limited environments.

What is the cloud pricing for these GPUs?

B300 SXM6 starts at $2.45 per hour, averaging $6.44 per hour across 7 offers. MI325X has no live cloud offers available.

How do FP32 performances differ?

MI325X delivers 1307 TFLOPS FP32, far exceeding B300's 90 TFLOPS. MI325X leads in full-precision computing.

Which is cheaper to rent, the B300 or the MI325X?

Cloud rental prices for both the B300 and MI325X vary by provider, configuration, and availability. This page shows live pricing from 25+ providers updated every 60 seconds. Scroll to the Live Cloud Pricing section to compare current rates.

How much VRAM does the B300 have compared to the MI325X?

The B300 has 288 GB of HBM3e memory. The MI325X has 256 GB of HBM3e memory.

Can I find B300 and MI325X GPUs available to rent right now?

Yes. This page shows real-time availability across 25+ cloud GPU providers. The Live Cloud Pricing section displays only in-stock offers with current pricing.

What is the main difference between the B300 and the MI325X?

The B300 uses the Blackwell Ultra architecture (2025) while the MI325X uses CDNA 3 (2024). The B300 delivers 1.7x the FP16 throughput and 2.0x the memory bandwidth of the MI325X.

B300 SXM6 vs MI325X: NVIDIA 288GB vs AMD 256GB | GPUPerHour