With blinding speed, precise timing and cat-like agility, I deftly pressed the Pause/Break button at precisely the right moment--finally.
The message is just, as Steve suggested, the bios boot screen text:
Intel (R) Management Engine BIOS Extension v6.0.3.0019
Copyright stuff here......
Intel (R) ME Firmware version 22.214.171.1248
Problem solved. Thanks to all for helping me with this.