12VHPWR Guard Open‑Source Tool Shuts Down PCs to Prevent RTX 5090 Power‑Connector Melting

A Reddit user known as CoolerThanNos released an open‑source utility called 12VHPWR Guard that monitors the per‑pin current of the 12VHPWR power connector on high‑end Nvidia RTX 5090 and RTX 5080 graphics cards. The software reads telemetry from the ITE IT8915FN sensor built into ASUS ROG Astral series cards via NVAPI/I²C (or optionally HWiNFO) and triggers an automatic Windows shutdown when any pin exceeds 9.5 A for more than 15 seconds. The default settings are deliberately conservative; users can adjust the current threshold and duration. The tool runs in the system tray, uses about 35 MB of RAM and 1 % of a single CPU core, and is available on GitHub for Windows systems only.

The utility is compatible solely with selected ASUS ROG Astral RTX 5080 and RTX 5090 models that expose individual pin current data. It does not prevent physical connector damage or address improper installation, serving only as a last‑ditch safety measure. Coverage of the release appeared in technology outlets in Switzerland, Germany and China.