The config.txt option is automatic at boot time. Most folks won't ever need it, 99.99% of HDMI display devices "just work" with a Raspberry with nothing special needed in /boot/config.txt or with the tvservice command.
Microprocessor, Raspberry Pi & Arduino Hacker
Mainframe database troubleshooter
2012-18: 1B*5, 2B*2, B+, A+, Z, ZW, 3Bs*3, 3B+
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