# rtcwake > Enter a system sleep state until specified wakeup time relative to your BIOS clock. > More information: . - Show whether an alarm is set or not: `sudo rtcwake -m show -v` - Suspend to RAM and wakeup after 10 seconds: `sudo rtcwake -m mem -s {{10}}` - Suspend to disk (higher power saving) and wakeup 15 minutes later: `sudo rtcwake -m disk --date +{{15}}min` - Freeze the system (more efficient than suspend-to-RAM but version 3.9 or newer of the Linux kernel is required) and wakeup at a given date and time: `sudo rtcwake -m freeze --date {{YYYYMMDDhhmm}}` - Disable a previously set alarm: `sudo rtcwake -m disable` - Perform a dry run to wakeup the computer at a given time. (Press Ctrl + C to abort): `sudo rtcwake -m on --date {{hh:ss}}`