Acpi\sny5001 Driver _best_ Here

Then, deep in a 2012 VAIO support thread (archived, in Italian), I found a real clue: "SNY5001 is the Sony Firmware Extension Parser. Without it, Windows can't talk to the EC (Embedded Controller) for fan curves and battery health."

I went back to Device Manager. The yellow triangle was gone. had moved to "System devices" and was now named Sony Firmware Extension Parser . acpi\sny5001 driver

Right-click → Update driver → "Windows couldn't find drivers." Standard. Then, deep in a 2012 VAIO support thread

"ACPI? That's power management stuff. SNY? That's Sony. 5001? No idea," I thought. had moved to "System devices" and was now

I went to Sony's support site (using the model number from the sticker under the laptop: ). I looked for "Driver - Firmware" and downloaded a file called Sony Firmware Extension Parser Driver (sometimes labeled "Sony Shared Library" or "VAIO Control Center").