Changing the Boot Menu Time-out
The boot menu time-out determines how long the boot menu is displayed before the default boot entry is loaded. It is calibrated in seconds.
If you want extra time to choose the operating system that loads on your computer, you can extend the time-out value. Or, you can shorten the time-out value so that the default operating system starts faster.
For Windows, you can use BCDEdit to change the default boot menu time-out value.
Using BCDEdit
To specify the boot menu time-out value, use the /timeout option:
bcdedit /timeout <timeout>
Use the /timeout option and specify the timeout value in seconds. For example, to specify a 15-second timeout value:
bcdedit /timeout 15