Press the power button and wait for the startup sequence

To turn your computer on, locate the power button — usually a round or rectangular button on the front or side of the tower, or on the keyboard if you have a laptop. Press it once and release. You do not need to hold it down.

After you press the button, the computer will take 30 seconds to two minutes to fully start up. During this time you will see lights turn on, hear the fan running, and watch the screen display startup messages or a logo. Let it finish this process completely before you try to use it. Interrupting the startup by pressing the button again can damage files.

Once the screen shows your desktop or login screen, the computer is ready to use. If you see a login screen with a username and password field, enter your credentials before proceeding.

Key Takeaways

  • The power button is usually on the front of the tower or the side of a laptop, and you press it once and release — do not hold it down.
  • Allow 30 seconds to two minutes for the computer to fully start up before you try to use it.
  • If you see a login screen, enter your username and password to access your account.
  • Turning the computer off during startup can corrupt files, so wait for the process to complete.
  • If the screen stays black after pressing the power button, check that the power cable is plugged in and the outlet has power.

Locate the power button on your specific computer type

Desktop computers usually have the power button on the front of the tower, either in the center or toward one of the corners. It is often labeled with a small circle or line symbol. On some older models, the button may be on the back of the tower near the power supply, though this is less common.

Laptop computers have the power button along the top edge of the keyboard, usually in one of the corners. On some models it is a separate button; on others it is integrated into the keyboard itself. Check your laptop's manual or the manufacturer's website if you cannot find it — the model number is usually printed on the bottom of the device.

All-in-one computers (where the screen and processing unit are built into one piece) typically have the power button on the bottom edge of the screen or on the back. Tablets and mobile devices have a power button on the side or top edge.

What to expect during the startup process

When you first press the power button, you will see the fan start running and lights illuminate on the computer. The screen may stay black for several seconds before displaying anything. This is normal — the computer is running through internal checks before showing you the desktop.

Next, you will see a manufacturer logo (Dell, HP, Lenovo, Apple, etc.) or a loading screen with a spinning circle or progress bar. This phase usually lasts 20 to 60 seconds. During this time, the computer is loading the operating system from the hard drive into memory.

Finally, the desktop appears with your wallpaper, taskbar, and any icons you have saved. If you have a username and password set up, you will see a login screen instead. Type your username, press Tab or click the password field, type your password, and press Enter. The desktop will then load.

Troubleshooting when the computer will not turn on

If you press the power button and nothing happens, the first step is to check the power cable. Make sure it is plugged firmly into both the back of the computer and the wall outlet. If the outlet has a switch, make sure it is turned on. Try plugging a lamp or phone charger into the same outlet to confirm the outlet itself has power.

If the outlet works but the computer still does not start, check whether there is a separate power supply switch on the back of the tower. Some desktop computers have a small switch near the power cable connection that must be set to the "on" position. Flip it and try the power button again.

If the screen stays black even after the computer starts up, the monitor may not be powered on or connected. Check that the monitor's power cable is plugged in and its power button is pressed. If the monitor has a cable running to the computer, make sure it is firmly connected to both the monitor and the computer's video port (usually labeled HDMI, DisplayPort, or VGA).

Shutting down properly after you are done

When you finish using the computer, do not straightforward press and hold the power button. This can cause data loss and file corruption. Instead, use the shutdown menu. On Windows, click the Start button in the bottom left, then click the power icon and select "Shut down." On Mac, click the Apple menu in the top left, then select "Shut Down."

The computer will close all open programs and save any unsaved work (or prompt you to save it). This process usually takes 10 to 30 seconds. Once the screen goes black and the fan stops running, the shutdown is complete and it is safe to unplug the power cable if needed.

If the computer freezes and will not respond to the shutdown menu, you can press and hold the power button for 10 seconds to force it off. This should be a last resort, as it can damage files. After a forced shutdown, wait 30 seconds before pressing the power button again to turn it back on.

Understanding sleep mode versus full shutdown

Most computers offer a sleep mode in addition to full shutdown. Sleep mode turns off the screen and reduces power use, but keeps the computer in a low-power state so it can wake up quickly when you press a key or move the mouse. Sleep mode is useful if you plan to return to your computer within a few hours.

To put your computer to sleep on Windows, click the Start button, click the power icon, and select "Sleep." On Mac, click the Apple menu and select "Sleep." The screen will go dark, but the computer will still be using a small amount of power.

Full shutdown, by contrast, closes all programs and turns off the computer completely. It uses no power (except for a tiny amount to keep the clock running) but takes longer to start back up. Use full shutdown if you will not use the computer for several hours or if you want to save the most power.

Frequently Asked Questions

How long should I wait before using the computer after turning it on?

Wait until the desktop fully loads and all startup programs have finished opening. This usually takes one to two minutes. If you try to open programs or files before the startup is complete, the computer may run slowly or freeze. You will know it is ready when the screen stops showing loading messages and the taskbar is fully visible.

Is it bad to turn off the computer by holding the power button?

Holding the power button forces the computer to shut down when ready without closing programs or saving files. This can corrupt data and damage the operating system. Only use this method if the computer is completely frozen and will not respond to the normal shutdown menu. After a forced shutdown, restart the computer and run a disk check if the startup seems slow.

Why does my computer take so long to start up?

Startup time depends on how many programs are set to run automatically when the computer starts, how full the hard drive is, and the age of the computer. Older computers or those with many startup programs may take three to five minutes. If startup suddenly becomes much slower, the hard drive may be failing or the computer may have a virus. Consider running a virus scan or consulting a technician.

Can I turn on my computer remotely?

Most computers cannot be turned on remotely unless they have a special feature called Wake-on-LAN enabled and a network connection. This requires technical setup and is not available on all computers. For most users, you must be physically present to press the power button. Check your computer's manual or manufacturer's website to see if this feature is available on your model.

What should I do if the screen stays black after startup?

First, check that the monitor is powered on and connected to the computer. If the monitor is on but still black, try pressing a key or moving the mouse — the computer may be in sleep mode. If the screen remains black and you hear the fan running, the graphics card or monitor connection may have failed. Try restarting the computer or connecting a different monitor to test.