In the AI arena, where trillions of calculations are performed every second, GPU stability directly determines the lifeline of a business. When your A100/H100 cluster suddenly experiences a sharp drop in performance, training tasks are frequently interrupted, or your rendering farm produces bizarre, distorted results, these seemingly random "minor glitches" are often caused by three core issues: memory corruption, NVLink connection failures, and GPU overheating.Statistics show that these three types of failures account for 78% of GPU downtime incidents in data centers, with an average loss per outage reaching as high as 230,000 yuan.
As a guardian of computing power backed by CRRC Group’s industrial-grade operations and maintenance standards and a team of over 100 chip-level engineers, Yuanjie Computing has partnered with CRRC Technology to launch the industry’s first "Guide to Troubleshooting Common GPU Issues," helping you accurately identify and quickly address problems to ensure uninterrupted computing power.
I. GPU Memory Failure: The "Silent Killer" in AI Training
1.1 Typical Symptoms and Identification Techniques
Visual Indicators:
Abnormal fluctuations in loss values during AI training, with convergence curves exhibiting irregular jagged patterns
Systematic deviations in deep learning inference results, with significant variations in the same model’s output across different batches
Random pixel blocks, texture anomalies, or flickering appear in 3D rendering outputs
System logs frequently record "ECC double-bit error" or "Uncorrectable memory error" alerts
Data Validation:

Industrial-Grade Diagnostics: CRRC Technology has applied high-speed rail signal integrity detection principles to develop a GPU VRAM signal analyzer capable of detecting nanosecond-level data anomalies, identifying potential failures 48 hours earlier than traditional software diagnostics.
1.2 Case Study: A100 Cluster VRAM Crisis at an Autonomous Driving Company
While training a BEV perception model, a leading autonomous driving company observed that training time suddenly increased from 8 hours to 26 hours, accompanied by a 15% drop in model accuracy. After diagnosis by Yuanjie Computing engineers, it was discovered that three HBM2e memory modules in an 8-card A100 cluster had micro-faults, manifested as ECC error rates exceeding safety thresholds under high load.
Solution: By adopting the "chip-level ball-replacement" technology jointly developed by CRRC and Yuanjie, the faulty memory chips were precisely replaced without replacing the entire GPU. This restored original performance while saving 870,000 yuan in hardware costs.
II. NVLink Connection Anomalies: The "Link Break Crisis" in Multi-GPU Coordination
2.1 Identification of Symptoms and Performance Impact
Topology Anomalies:
Multi-GPU training tasks cannot fully utilize all computing units, resulting in severe imbalance in GPU utilization
nvidia-smi topo -mCommand-line output indicates abnormal NVLink connection status as "PIX" or "NVL"System logs record warnings such as "DOE timeout errors" or "NVLink protocol errors"
Abnormally high proportion of communication time during large-scale model training (normal <15%, abnormal >40%)
Bandwidth Testing:

CRRC Standard: Drawing on the reliability standards for high-speed train car connectors, the NVLink health scoring system jointly developed by Yuanjie and CRRC classifies connection stability into 5 levels, ensuring multi-GPU collaboration efficiency >95%.
2.2 Case Study: "Microsecond-Level Losses" at a Financial Quantitative Firm
A 40-card H100 cluster at a top-tier quantitative hedge fund encountered unstable NVLink connections during high-frequency trading model training. While the system appeared to be operating normally, actual NVLink bandwidth was measured at only 62% of the rated value. This resulted in prolonged model training times, causing the firm to miss critical market windows and incurring potential daily revenue losses exceeding 3 million yuan.
Through Yuanjie Computing’s 72-hour emergency replacement service, which utilized CRRC’s industrial-grade NVLink connector solution, the cluster restored 98.7% of its theoretical bandwidth, with a return on investment (ROI) realized within three weeks.
III. GPU Overheating: The "Slow-Acting Poison" of Computing Power Decline
3.1 Multidimensional Manifestations of Abnormal Temperatures
Direct Indicators:
nvidia-smiMonitoring shows core temperatures consistently exceeding 85°C (the safety threshold for the Hopper architecture is 83°C)Fan speed reaches over 95% but still fails to stabilize temperatures
System triggers automatic throttling protection, with GPU clock speeds significantly below base frequency
Abnormal local temperatures within the cabinet; infrared thermal imaging reveals thermal dead zones
Indirect Signs:
Computing performance fluctuates periodically, with performance dips occurring every 2–3 hours
Server logs record "thermal throttling" or "temperature trip point" events
GPU failure rates in the middle of the rack within the same cluster are 3.2 times higher than those at the edges
Thermal grease between the heat sink and the GPU core shows signs of cracking or leakage
CRRC Cooling Solution: Applying high-speed rail traction transformer cooling technology, the liquid-cooling/air-cooling hybrid system developed by Yuanjie Computing can maintain H100 full-load temperatures within the optimal range of 72±3°C, extending GPU lifespan by 40% compared to traditional solutions.
3.3 Emergency Response: The "Temperature Crisis" in a Film Rendering Farm
While rendering special effects shots, a major visual effects company faced collective overheating and throttling across its 400-card A100 cluster during the summer heatwave, putting project delivery at risk of delay. On-site inspection by Yuanjie Computing engineers revealed a design flaw in the data center’s cold aisle layout, causing hot air recirculation.
Emergency Solution: Implementation of CRRC-standard cooling retrofit within 72 hours:
Redesigned cabinet airflow layout and added deflector plates
Replace thermal paste with a higher thermal conductivity grade to improve contact between GPUs and heat sinks
Optimized fan control strategies using CRRC’s intelligent temperature control algorithm
Deploy a real-time temperature monitoring and early warning system
The project was delivered on schedule. This retrofit also saved the company 370,000 yuan in annual electricity costs and increased the cooling system’s availability to 99.95%.
IV. Professional Solutions: Where Industrial Standards Meet Computing Precision
Faced with these complex failures, ordinary IT operations teams are often at a loss. Yuanjie Computing has partnered with CRRC Technology to deeply integrate 30 years of maintenance experience—marked by zero major accidents in high-speed rail equipment—with chip-level GPU repair technology, creating a rare, full-stack support system in the industry:
4.1 Chip-Level Rebuilding Technology
Equipped with Swiss SolderStar BGA rework stations and U.S. hot-air rework systems
Supports reballing and reconstruction of GPU chips with 16nm/5nm processes
Precise replacement of H100 memory chips with a 99.3% success rate
4.2 Industrial-Grade Diagnostic System
Transfer of CRRC high-speed rail signal integrity testing technology to the GPU signal layer
In-house developed NVLink topology analyzer with accuracy up to 0.1 ns
Power Quality Analysis System capable of detecting ripple anomalies at the 10mV level
4.3 Nationwide Rapid Response Network
Four major spare parts centers in Beijing, Shanghai, Guangzhou, and Shenzhen, with 98% spare parts coverage
50+ certified engineers providing 24/7 technical support
72-hour emergency connector replacement commitment (industry average: 7 days)
V. Preventive Maintenance: The Intelligent Operations Revolution Aiming for Zero Failures
"On the battlefield of 100 billion calculations per second, we make zero failures possible" — The Yuanjie Computing Intelligence Maintenance Center not only provides fault repair but is also dedicated to preventing failures from occurring. We recommend the following maintenance strategies:
Quarterly Health Checks: GPU health assessments based on CRRC’s equipment lifecycle management model
Predictive Maintenance Plan: Utilizing AI to analyze historical operational data and issue early warnings of potential failures 14–30 days in advance
Energy Efficiency Optimization Service: Reducing abnormal power consumption by 30% through power supply module reconfiguration, extending GPU lifespan
Expert Recommendation: For mission-critical GPU clusters, we recommend implementing the "1+1+N" assurance strategy: 1 quarterly in-depth inspection + 1 real-time monitoring system + N spare critical components. The Computing Power Assurance Service Package, jointly launched by Yuanjie Computing Power and CRRC Technology, has already helped 287 enterprises achieve a 99.99% availability rate for their GPU infrastructure.
Take Action Now to Protect Your Computing Assets
When your AI training suddenly slows down, rendering outputs become abnormal, or data center temperature alerts trigger, your GPUs may be sending you a distress signal. Yuanjie Computing, in partnership with CRRC Technology, provides end-to-end services ranging from fault diagnosis to chip-level repairs:
Free Initial Diagnosis: Submit your GPU runtime logs to receive a professional diagnostic report Emergency
Response: Components dispatched from four regional service
centers for rapid on-site repairs within 72 hours Maintenance-as-a-Service: Flexible subscription-based plans with customizable maintenance tiers
On the battlefield of hundreds of billions of calculations per second, we make zero downtime a reality.
Service Hotline: 400-0896-016
Online Diagnosis: Click for details
