100 Firmware Hot ((hot)) | Bu40n

is widely considered the "gold standard" or "hot" version because it is the most compatible revision for ripping 4K UHD discs. While newer versions like 1.04 or 1.05 exist, they often include "downgrade protections" or encryption that prevent them from working with third-party ripping tools. Why Firmware 1.00 is Highly Valued

Later firmware revisions reduce the spindle motor speed during idle and error recovery. Version 1.00 keeps the disc spinning faster for longer, increasing friction-based heat and motor driver temperature.

Scouring the MakeMKV and Reddit r/makemkv communities, the consensus is clear:

To keep the drive "cool," enthusiasts often use it in an external enclosure with better airflow or place the drive on a laptop cooling pad during long sessions. How to Get Firmware 1.00

If you have a BU40N on 1.00 firmware, keep it that way and flash to MK 1.03 for full UHD ripping. If you're looking for that firmware, check the MakeMKV "Ultimate UHD Drives Flashing Guide" thread.

The Ultimate Guide to LG BU40N 1.00 Firmware : Why Older is Sometimes "Hotter"

This specific version was "UHD Friendly." It didn't strictly enforce the newest copy protections, allowing enthusiasts to use specialized software to "backup" their expensive 4K discs to digital servers like Plex or Jellyfin. The "Hot" Commodity As word spread, version 1.00 became "hot" in two ways: High Demand: