I see this message -
You can now remove the boot DVD or USB stick. The system memory is goin gto be wiped in a few seconds... Display might be corrupted during this operation. If the system does not power off automatically in a few seconds, it may mean the memory wiping has failed.
Please remove the USB flash drive and press ENTER to continue:live-boot: caching reboot files... [ 2468.592498] Starting new kernel
following the prompt I remove the Tails live USB, and press enter. Then nothing happens. I can press and hold the power button to force the computer to shutdown, but I think this would interrupt the RAM memory wipe.
So, how long should it take to wipe 16gb RAM / system memory at shutdown?
this question is a nice discussion of other approaches to memory wiping, but doesn't speak to this particular situation in Tails.