While people were busy debating failures of the 12V-2x6 / 12VHPWR plugs, we were shown a PC with a melted cable and a GeForce RTX 5070. Oddly enough, this one wasn’t traced to an NVIDIA plug defect or a faulty GPU. Instead, the owner had connected the card’s bundled 16-pin adapter to a single PCIe lead from the PSU, using a passive 1x8 → 2x8 splitter.
That passive split meant both halves of the 16‑pin adapter drew current through one cable. Predictable result: overheated wiring and melted insulation. It’s a blunt, annoying lesson — don’t treat a single PSU cable as if it were two. Cheap, third‑party split adapters (often from China) are common in these stories and, in practice, they can be risky when used with modern, high-draw GPUs.
If nothing else, this incident is another practical reminder: check how many separate PSU cables you’re using for a 16‑pin connection (PSU, GPU, PCIe context) before power-up. Mistakes like this aren’t mysteries; they’re avoidable.