The toolbar located at the top of the PCBox window (right below the menu bar) has two purposes: it provides quick actions for the emulated machine on its left hand side, and displays status information on its right hand side.
Pause emulation of the machine. Press again to resume emulation.
Emulation is automatically paused when the emulated machine enters ACPI sleep mode.
Force a reset of the emulated machine. Requires confirmation, which can be disabled by checking the Don’t show this message again box.
Send a Ctrl+Alt+Del (left-most icon) or Ctrl+Alt+Esc (right-most icon) key combination to the emulated machine. You can alternatively press Ctrl+F12 to send a Ctrl+Alt+Del combination.
Open the Settings window to configure the emulated machine.
The right hand side of the toolbar displays status information, such as:
Emulation speed in percentage. If this number stays consistently below 100%, your host system is not keeping up with emulating the configured hardware.
Mouse state (captured or released) if a mouse is enabled.
Pause indicator if emulation is paused.