1. High-Speed Interconnect Empowering AI

AI and High-Performance Computing (HPC) have become the foundation of the world’s most demanding compute environments. From large-scale model training to real-time inference, modern AI workloads require massive data movement between GPUs, CPUs, accelerators, memory devices, and storage. This continuous data exchange is enabled by High-Speed Interconnects, which constitute the invisible "nervous system" within every AI cluster. Data movement and interconnects are the cornerstones of AI computing power.

Current AI infrastructure performance is highly dependent on the following key technologies:

• PCIe Gen5/Gen6 Links: Achieving ultra-low latency communication between GPU-to-GPU and GPU-to-CPU.
• CXL-based Memory Expansion: Supporting disaggregated and pooled memory architecture.
• Diversified Cable Assemblies: Including DAC (Direct Attach Copper), AEC (Active Electrical Cable), ACC (Active Copper Cable), and AOC (Active Optical Cable), used to interconnect accelerators, switches, and compute nodes within hyperscale data centers.

As AI model sizes scale to trillions of parameters, bandwidth requirements grow exponentially. Electrical link rates have reached 64GT/s, and optical links have reached 224Gbps PAM4; furthermore, both electrical and optical links are evolving towards even higher rates, making acceptable signal margins extremely narrow. In such high-frequency channels, even slight signal degradation can lead to significant reductions in training throughput or severe system downtime.

To ensure continuous stability of system performance, every high-speed cable must be able to withstand the following physical and electrical challenges:

• High-frequency Insertion Loss: Addressing the attenuation of high-frequency signals along the transmission path.
• Crosstalk in High-density Routing: Suppressing interference between signals in compact routing environments.
• Environmental Thermal Stability: Able to withstand temperature fluctuations between racks and across various operating environments.
• Long-term Stability Stress: Undergoing long-term electrical or optical-physical stress tests under continuous high-load operations.

2. Test Challenges in High-Speed Cable Manufacturing

• Approaching Physical Limits: The PAM4 signaling of PCIe 6.0 cables imposes strict requirements on Signal-to-Noise Ratio (SNR); the manufacturing process must undergo rigorous joint verification of BER (Bit Error Rate) and SI (Signal Integrity).
• Channel Scaling Pressure: Cables contain hundreds of physical channels; traditional single-channel testing can no longer meet the requirements of large-scale mass production.
• Complexity of Active Interconnects: The integrated retimers/equalizers within AEC and ACC require complex tuning of Pre-emphasis and Receiver Equalization (Rx EQ); testing involves not only electrical parameters but also link-layer protocol handshaking.
• Production Throughput (UPH): While maintaining high-precision testing, automated means must be used to optimize test time and improve test efficiency.

3. Solution by Semight Instruments

The high-speed cable test solutions by Semight Instruments are tailored for the next generation of AI infrastructure. We are committed to ensuring that every interconnect component meets the stringent standards for bandwidth, reliability, and stability required for large-scale deployment, providing a robust physical layer guarantee for global AI computing clusters.

Targeting PCIe Gen6 and its evolving standards, Semight introduces the ABT2010 High-Speed BERT (Bit Error Ratio Tester) platform:

• Full Protocol Coverage: Natively supports dynamic full-rate switching from 2.5GT/s to 64GT/s, with backward compatibility for all PCIe specifications.
• Extremely High Test Density: A single system supports up to 64 Lanes (i.e., 128 differential pairs), significantly increasing the UPH per station.
• Superior Link Compensation: Possesses the capability to handle a Die-to-Die loss budget of up to 40dB in PCIe Gen6 environments, ensuring signal recovery under extreme link conditions.
• Fully Automated Equalization Training: Supports hardware-level Link Training, allowing independent configuration of Tx/Rx equalization parameters for each channel.
• Modularity and Thermal Management: Utilizes a customizable daughter card architecture to adapt to different DUT types, combined with precision air-cooling technology to ensure thermal stability under long-duration full-load testing.

This test platform possesses the following core advantages:

• Forward-looking Architecture: Directly benchmarks against 112G/224G applications and PCIe Gen5/Gen6, meeting current AI/HPC needs and adapting to future technical roadmap evolution.
• Parallel Testing Efficiency: The multi-channel parallel architecture significantly reduces the test cost per lane (Cost per Lane).
• Intelligent Tuning: Built-in signal adaptive optimization algorithms automatically match the best signal compensation parameters.
• Low Maintenance Cost: Modular design allows for rapid on-site replacement of key components, minimizing the risk of downtime.

4. Conclusion

Semight Instruments delivers a comprehensive, scalable, and production-proven high-speed cable testing ecosystem tailored for the needs of modern AI infrastructure. As data rates increase and interconnects become more sophisticated, our solutions ensure that every cable meets stringent performance and reliability standards. With Semight’s High-Speed Cable Test Solution, manufacturers and data center integrators gain complete confidence that every interconnect in their architecture is rigorously tested, validated, and ready to perform at scale.