NAVIgator: Exploring the Voltage Limits of AMD NAVI GPUs for Energy Efficient Computing
Maria Trakosa, Odysseas Chatzopoulos, George N. Papadimitriou, Dimitris Gizopoulos · 2025
As semiconductor fabrication scales to smaller technology nodes, process variation has become a significant challenge, affecting power consumption, thermal behavior, and voltage stability in microprocessors and GPUs. Conservative voltage guardbands are traditionally used to ensure reliable operation under worst-case process, voltage, and temperature (PVT) variations, but they lead to excessive power consumption. Reducing the supply voltage, while maintaining a fixed frequency, has emerged as a promising technique for improving energy efficiency without sacrificing computational correctness and performance. While extensive research has been conducted on reducing the voltage levels in CPUs and NVIDIA GPUs, AMD GPUs remain relatively unexplored, particularly in terms of process variation. This variation, inherent in semiconductor manufacturing, results in differences in power efficiency, thermal characteristics, and voltage stability even among identical GPUs from the same production batch. In this paper, we present an extensive study on voltage scaling beyond nominal conditions for three modern AMD NAVI GPUs (i.e., RX 7600 XT, 7700 XT, and 7800 XT) executing both conventional benchmarks and PyTorch-based machine learning workloads. We evaluate and present power savings and execution stability under undervolted conditions, highlighting the impact of chip-to-chip variability. Our findings contribute to a deeper understanding of undervolting in AMD GPUs and its dependence on process variation, providing insights into practical power-saving strategies.