What are the interconnect speeds for the NVIDIA H100 PCIe, SXM, and NVL GPUs?
NVIDIA H100 GPU Interconnect Speeds: PCIe, SXM, and NVL Explained
The NVIDIA H100 GPU, built on the advanced Hopper architecture, offers different interconnect speeds and configurations across its PCIe, SXM, and NVL variants. Understanding these differences helps optimize GPU selection for AI, HPC, and data center workloads.
NVIDIA H100 PCIe Interconnect Speeds
The NVIDIA H100 PCIe GPU leverages PCI Express Gen 5.0 for system connectivity and NVLink for GPU-to-GPU communication:
- PCIe Interface: PCIe Gen 5.0 (128 GB/s bi-directional total bandwidth)
- NVLink: 600 GB/s total bandwidth per GPU (bidirectional)
The PCIe variant is ideal for systems requiring flexible integration and compatibility across a wide range of server platforms.
NVIDIA H100 SXM Interconnect Speeds
The NVIDIA H100 SXM (System-on-Module) GPUs use NVIDIA NVLink 4.0 technology, designed specifically for maximum GPU-to-GPU communication speed and scalability:
- NVLink: Up to 900 GB/s total bandwidth per GPU (bidirectional)
- NVSwitch: Enabled via NVIDIA NVSwitch architecture, providing extremely high-bandwidth, low-latency inter-GPU communication within NVIDIA DGX H100 systems.
The SXM variant is optimized for scalability and intensive AI training workloads, commonly deployed in NVIDIA DGX H100 and similar high-performance computing environments.
NVIDIA H100 NVL Interconnect Speeds
The NVIDIA H100 NVL is specifically designed for large-scale AI inference workloads, particularly language model inference. It features two GPUs connected via NVLink bridge:
- NVLink Bridge: Offers ultra-high NVLink connectivity with up to 600 GB/s bidirectional bandwidth between the two GPUs.
- PCIe Interface: PCIe Gen 5.0 for system-level connectivity.
The NVL variant is optimized for demanding AI inference tasks (such as large language models), providing exceptional performance and efficiency.
Quick Reference Table for NVIDIA H100 Interconnect Speeds
| GPU Variant | NVLink Bandwidth | PCIe Version | PCIe Bandwidth |
|---|---|---|---|
| H100 PCIe | 600 GB/s | PCIe Gen 5.0 | 128 GB/s |
| H100 SXM | 900 GB/s | PCIe Gen 5.0* | N/A (module form factor) |
| H100 NVL | 600 GB/s (GPU-pair connectivity) | PCIe Gen 5.0 | 128 GB/s |
*Note: SXM modules are integrated onto specialized carrier boards (such as NVIDIA DGX systems), and thus the PCIe interface is internal and not typically exposed externally.
Choosing Between PCIe, SXM, and NVL Variants
- H100 PCIe: Best for versatile deployments, broad server compatibility, and easier integration into existing data centers.
- H100 SXM: Ideal for maximum performance, scalability, and high-density AI/HPC clusters.
- H100 NVL: Optimized specifically for large-scale AI inference workloads, particularly large language models.
Selecting the appropriate NVIDIA H100 GPU variant ensures efficient utilization and maximum performance for your specific computing and AI needs.