How to Automatically Power On Your PC at a Set Time in BIOS [RTC Alarm]

“I want my PC to turn on automatically every morning at a set time,” or “I want it to power on after running updates or backups overnight” — that’s exactly what the RTC Alarm feature built into the BIOS (UEFI) can do for you.

Since this is configured from the motherboard’s BIOS screen rather than from within Windows, it might sound intimidating — but the steps themselves are simple. This article walks through the process step by step using BIOS screenshots, from turning the feature on to turning it back off.

　

What you’ll learn in this article

• How to open the BIOS (UEFI) screen
• How to set up RTC Alarm to power on your PC automatically at a specific time
• How to turn off the automatic power-on setting
• Things to know before you set it up

　

How to open the BIOS (UEFI) screen

Turn on your PC, and during the brief moment the manufacturer’s logo is displayed, repeatedly press the designated key to open the BIOS (UEFI) screen. The key varies by manufacturer, so use the table below as a reference.

Manufacturer	BIOS Key
ASUS	F2 or Delete
Dell	F2
HP	F10 or Esc
Lenovo	F1 or F2
MSI	Delete
Acer	F2 or Delete

※ If the timing is off, Windows will simply boot as usual. If that happens, restart your PC and try again. For reference, on the author’s machine the Delete key was the one that opened the BIOS screen.

　

The BIOS main screen

Once you enter the BIOS, you’ll see a screen like the one below. The design varies by device, but the overall layout is generally similar.

The bottom-right corner of the screen shows the key controls. Before moving on, let’s go over the basic operations.

Key	Function
← →	Switch between screens (tabs)
↑ ↓	Select an item
Enter	Confirm selection
+/-	Increase or decrease a value
F1	Show help
F5	Load optimized defaults
F7	Discard changes
F10	Save and exit
Esc	Go back / exit

　

What Is RTC Alarm? How Automatic Power-On Works

Every PC has a built-in clock called the RTC (Real Time Clock), which keeps track of the time and date continuously using its own dedicated battery. RTC Alarm is an alarm feature that uses this RTC to automatically turn the PC on at a date and time you specify.

　

　

Steps to Set Up Automatic Power-On

1. Open the Power Tab

Use the arrow keys to move to the Power tab at the top of the screen.

2. Open APM Configuration

Inside the Power screen you’ll find an item called APM Configuration. Select it with the arrow keys and press Enter to open the detailed settings screen.

3. Select Power On by RTC Alarm

In the APM Configuration screen, use the arrow keys to move down to Power On by RTC Alarm and press Enter.

4. Change It to Enabled

A Disabled / Enabled selection will appear. Use the arrow keys to highlight Enabled and press Enter to turn the feature on.

5. Set the Date and Time to Power On

Once enabled, the following items appear below Power On by RTC Alarm. These let you set exactly how often, and at what time (hour, minute, second), the PC should turn on automatically.

Item	Description
RTC Alarm Date	Sets the date (interval) to power on
RTC Alarm Hour	Sets the hour to power on
RTC Alarm Minute	Sets the minute to power on
RTC Alarm Second	Sets the second to power on

Move to the item you want to set using the arrow keys, then use the + or – keys to increase or decrease the value.

※ On most BIOSes, setting RTC Alarm Date to “0” makes the PC power on every day, while setting it to 1–31 makes it power on once a month on that date. Behavior can vary by manufacturer and BIOS version, so it’s a good idea to confirm it actually works after configuring it.

6. Save the Settings

That completes the automatic power-on setup. Finally, save your changes. Press Esc to go back and select the Save & Exit tab, or simply press F10 to bring up the save screen directly.

Selecting Save Changes and Reboot brings up a confirmation screen — choose [Yes] and restart to apply the settings.

　

　

How to Turn Off the Automatic Power-On Setting

If you no longer need this setting, follow the same steps to enter the BIOS and open APM Configuration from the Power screen.

With Power On by RTC Alarm already set to Enabled, select this item.

When the options appear, use the arrow keys to change it to Disabled.

Once it’s set to Disabled, the RTC Alarm Date/Hour/Minute/Second fields will disappear. After confirming the setting has been turned off, press F10 to save your changes and restart.

　

Things to Keep in Mind

• On laptops, RTC Alarm may not trigger an automatic power-on when running on battery alone. Make sure the laptop is plugged into AC power.
• Depending on how you shut down (e.g., Fast Startup vs. a full shutdown), RTC Alarm may not work correctly. If it isn’t powering on as expected, also check your Windows Fast Startup setting.
• BIOS item names (such as Power On by RTC Alarm) and the available settings can vary slightly by motherboard and manufacturer. If your screen doesn’t match exactly, look for an item with a similar name.
• Before saving, it’s a good idea to double-check that you haven’t accidentally changed any other settings (such as Wake on WLAN) along the way.