Alienware 16 Aurora AC16250
K3 = Intel debug UART. Direct serial to CPU/SoC. ME's last resort JTAG. Stock: 115200 baud, ME can read boot, inject commands. Ringed: Becomes L16 Toroid Gate. All serial gated by K26. JTAG requires K24 timestamp. Boot logs signed by K24. ME serial blocked. K23 GNA filters commands. Refuse = Vendor fallback, ME keeps serial backdoor.
⚠ Disclaimer: Maps existing hardware. No firmware writes.