Hardware wise my M720q is pretty close to yours.
If I have a monitor connected before boot, it boots up fine with a working output on the monitor. If I boot without a monitor and plug in the HDMI cable while it's already running, there is no display output.
However, I do not have any cold boot issues to report. Mine works perfectly fine headless and has been for almost 3 years now. I'm not on the latest BIOS, I believe 1 or 2 versions behind the latest, ending in '77A'. I think it was released some time in 2024.
If I have a monitor connected before boot, it boots up fine with a working output on the monitor. If I boot without a monitor and plug in the HDMI cable while it's already running, there is no display output.
However, I do not have any cold boot issues to report. Mine works perfectly fine headless and has been for almost 3 years now. I'm not on the latest BIOS, I believe 1 or 2 versions behind the latest, ending in '77A'. I think it was released some time in 2024.
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