Windows NT 5.0 refers to the internal version number used for Windows 2000, so this clip is widely recognized as the Windows 2000 startup sound. It comes from Microsoft's operating system era around the turn of the millennium, when startup audio became a memorable part of the PC experience. Online, the sound kept circulating in retro computing videos, operating system comparisons and nostalgia edits. People still use it because one short chime instantly evokes old desktops, office computers and early internet culture.