Ever since the default changed to never blanking the screen, and after I whined in comment #18 above, I have been running this in /etc/default/grub:
GRUB_CMDLINE_LINUX_DEFAULT="<other stuff> consoleblank=300 <other stuff>"
always save a copy of grub first, and do "sudo update-grub afterwards", then re-boot.
Ever since the default changed to never blanking the screen, and after I whined in comment #18 above, I have been running this in /etc/default/grub:
GRUB_CMDLINE_ LINUX_DEFAULT= "<other stuff> consoleblank=300 <other stuff>"
always save a copy of grub first, and do "sudo update-grub afterwards", then re-boot.