PCIe Interface
Connectivity
DEFINITION
The connection standard used to attach GPUs to the motherboard, determining data transfer speeds between CPU and GPU.
OVERVIEW
PCIe (Peripheral Component Interconnect Express) is the standard interface for connecting GPUs to computers. The generation (3.0, 4.0, 5.0) and lane width (x8, x16) determine the maximum bandwidth.
TECHNICAL DETAILS
PCIe 4.0 x16 provides ~32 GB/s bidirectional bandwidth, while PCIe 5.0 x16 doubles that to ~64 GB/s. The interface affects how quickly data can be transferred between system RAM and GPU memory. For most deep learning workloads, PCIe 4.0 x16 is sufficient, but data-intensive applications benefit from PCIe 5.0 or NVLink.
COMMON USE CASES
- Loading datasets from system RAM to GPU
- Multi-GPU systems without NVLink
- Inference servers with frequent model swapping
- Data preprocessing pipelines
- Workstations with multiple GPUs