Recently, foreign researcher Kate successfully used voltage fault injection technology to unlock the previously disabled VRAM and compute units on NVIDIA CMP 170HX mining cards, transforming cards labeled with 8GB VRAM into A100-level compute cards with 80GB VRAM.
The CMP 170HX is a mining product launched by NVIDIA, using the same GA100 GPU as the data center A100, but with many hardware features disabled at the factory.
This time, instead of soldering new VRAM chips, the method involves re-enabling the HBM memory that was already present but disabled within the mining cards. Kate stated that the 8GB version actually contains around 80GB of HBM, while another 10GB version contains approximately 40GB.
Previously, software tools were able to increase the available VRAM on some CMP 170HX cards to 64GB, but they still couldn't fully remove limitations on compute units, PCIe interfaces, and other aspects.
Kate targeted the electronic fuse controller inside the GPU responsible for configuring hardware features. By bypassing write restrictions through voltage fault injection and modifying relevant configurations, she re-enabled the previously disabled VRAM and streaming processors.
Out of ten tested 8GB mining cards, nine successfully enabled the full 80GB of VRAM, while one could only use 64GB. Some modified cards also restored features like PCIe 4.0 and NVLink, although not all functions have been fully verified.
In terms of performance, a successfully unlocked mining card achieved approximately 85.9 TFLOPS in OpenCL FP16 FMA tests, higher than the researcher's measured ~72.5 TFLOPS for the A100, representing an 18% lead. Kate attributes this to the modified card enabling around 120 to 126 SM groups, whereas the standard A100 only enables 108.
The second-hand market price for the CMP 170HX is around several thousand dollars. The 8GB version currently costs about $3,000 (Fast Technology note: approximately 20,000 RMB), while some A100 80GB PCIe versions are quoted at over $20,000 (Fast Technology note: approximately 133,350 RMB).
The researcher stated that the issue was disclosed to NVIDIA's product security team before publishing the results. This modification involves hardware operations and irreversible configuration changes, carrying a risk of damaging the graphics card, and is not suitable for ordinary users to attempt.