I finally looked up nsvc.exe on another machine. No results. I searched forums in Russian, Mandarin, and Portuguese. In a Romanian cybersecurity archive from 2016, I found a single mention: “nsvc – network system vector cache. Present in modified 8.1 builds. Do not connect to public Wi-Fi. Do not share drives. If clock jumps, isolate.”
This OS is designed for one purpose:
Despite the flashy name, is not an official Microsoft product. It is a heavily modified, "de-bloated," and compressed version of Microsoft’s Windows 8.1 Professional. Windows 8.1 Pro Super Lite Extreme 32 64-bit
When I rebuilt that machine a month later—new SSD, fresh Linux—the first thing I saw after boot was a single pixel of light in the top-left corner. I thought it was a stuck pixel. But it blinked. Slowly. Long-short-long. I finally looked up nsvc