How to enter the BIOS or CMOS setup

Because of the wide variety of computer and BIOS manufacturers over the evolution of computers, there are numerous ways to enter the BIOS or CMOS Setup. Below is a listing of most of these methods, as well as other recommendations for entering the BIOS setup.

Note: This document does not help if you cannot enter the BIOS or CMOS setup because of a password.

New computers

Computers manufactured in the last few years allow you to enter the BIOS setup using one of the five keys shown below during the boot process. Typically it is one of the first three keys.

• F1
• F2
• DEL
• ESC
• F10 *

* F10 is also used for the boot menu. If F10 opens a boot menu, your setup key is likely F2.

You will know when to press this key when you see a message similar to the example below as the computer is booting. Some older computers may also display a flashing block to indicate when to press the F1 or F2 keys.

Press <F2> to enter BIOS setup

Tip: If your computer is a new computer and you are unsure of what key to press when the computer is booting, try pressing and holding one or more keys on the keyboard to cause a stuck key error. Once you get this error, you should have the option to continue or enter setup.

Once you have successfully entered the CMOS setup, you should see a screen similar to the example below.

How do I change and save changes in CMOS setup?

Once in CMOS setup, the method for changing the settings often depends on the BIOS manufacturer. Typically you can change the settings by using the arrow keys to move to the option you want to change. Press Enter to select what to change and then use the arrow keys to select a new value. Some manufacturers may have you press the Page up and Page down keys to change the values.

Tip: All manufacturers list the steps on how to navigate on the bottom or right-hand side of the screen.

I cannot change the values to a setting I want to use.

If you are trying to change the clock settings, speed settings, or other setting and do not have an available option, it is because it is not supported by the motherboard. If you believe it should be supported, you may need a BIOS update.

Older computers

Unlike the computers of today, older computers (before 1995) had numerous different methods of entering the BIOS setup. Below is a listing of key sequences to press as the computer is booting to enter setup.

• CTRL + ALT + ESC
• CTRL + ALT + INS
• CTRL + ALT + ENTER
• CTRL + ALT + S
• PAGE UP KEY
• PAGE DOWN KEY

ACER BIOS

If your computer cannot boot or you want to restore the BIOS back to its bootable settings and your computer uses an ACER BIOS, press and hold the F10 key as you turn on the computer. While continuing to hold the F10 key, you should hear two beeps indicating that the settings are restored.

AMI BIOS

Older AMI BIOS could be restored back to bootable settings by pressing and holding the Insert key as the computer is booting.

BIOS or CMOS diskettes

Early 486, 386, and 286 computers required a floppy disk in order to enter the BIOS setup. These diskettes may be referred to as ICU, BBU, or SCU disks. Because these diskettes are unique to your computer manufacturer, you must obtain the diskettes from them. See the computer manufacturers list for contact information.

Early IBM computers

Some early IBM computers require you to press and hold both mouse buttons as the computer boots to enter the BIOS setup.

Other suggestions

Finally, if none of the above suggestions help get you into your CMOS setup, you can cause a stuck key error, which causes the CMOS setup prompt to appear and remain until you press a key to continue. To do this, press and hold any key on the keyboard and do not let go (you may get several beeps as you are doing this). Keep pressing the key until the computer stops booting and you have the option to enter setup.

CMOS

Alternatively referred to as a Real-Time Clock (RTC), Non-Volatile RAM (NVRAM) or CMOS RAM, CMOS is short for Complementary Metal-Oxide Semiconductor. CMOS is an on-board semiconductor chip powered by a CMOS battery inside computers that stores information such as the system time and date and the system hardware settings for your computer. The picture shows an example of the most common CMOS coin cell battery used in a computer to power the CMOS memory.

A Motorola 146818 chip was the first RTC and CMOS RAM chip to be used in early IBM computers. The chip was capable of storing a total of 64 bytes of data. Since the system clock used 14 bytes of RAM, this left an additional 50 bytes of space that was available for IBM to store system settings. Today, most computers have moved the settings from a separate chip and incorporated them into the southbridge or Super I/O chips.

How long does the CMOS battery last?

The standard lifetime of a CMOS battery is around 10 Years. However, this can vary depending on the use and environment that the computer resides. When the battery fails the system settings and the date and time will not be saved when the computer is turned off until the battery has been replaced.

ESC

 

 

1. Short for escape, esc is a key located on the top-left of a computer keyboard that allows a user to cancel or abort operations.

• Computer keyboard help and support.

2. Escape is also shorthand for an escape character, an escape is a single backward slash ( \ ) in Linux, programming, and regular expressions that perform a special function or to have a character treated as plain text and not a function. Below are some examples of how an escape could be used.

\*

The above example would treat the asterisk as a plain text asterisk and not as a wild card or metacharacter.

\.

This next example is similar to the first example because the period is also a wild card, which represents any single character. So, if you need match a period and not every character you must escape it.

\" or \'

The above example would treat the quote character as a quote character and not a beginning or end container. For example, in programming languages such as Perl this is required if you're printing text to a file or the screen that contains a quote. In other words, the command print "This is a \" quote."; would print This is a " quote without escaping the quote in the middle you would receive an error.

\

When a filename or directory needs a space in Linux you can use a backward slash followed by a space, to escape the space in a name. If this isn't done, Linux will treat anything after the space as an option or additional command.

\n

Finally, escape characters are also used in escape sequences, to create a function or command. For example, the above \n would create a newline character to the file or screen. See our escape sequence definition for additional examples.

3. Short for escalation, esc is used to describe or refer to an escalation number dealing with an important customer related issue

No display on the monitor

 

 

Tip: The following is monitor troubleshooting and not for users who get readable picture when it is first load but then gets distorted when opening Windows.

Monitor is not on

Make sure the monitor is on. If no power LED (green or orange light) is seen on the monitor display try pressing the power button until it comes on. If no light comes on after several attempts continue to below connections not connected properly.

Computer is asleep

If your computer monitor was on and you stepped away from the computer and upon returning it was black it's likely that the computer is asleep. Try moving your mouse, clicking the mouse buttons, or pressing any key (space bar) on the keyboard to wake it up.

Connections not connected properly

 

Make sure that you are connecting the monitor to the back of the computer in the 15-pin connector as shown to the right or older computer 9-pin connection.

Note: Newer computers may be using a DVI or HDMI cable for the monitor.

If the computer is properly plugged in, make sure it is getting power.

If you are not receiving power from a known working wall outlet and if the power cord is removable, replace it with the one connected to the computer and power on the monitor again. If the monitor still does not get power or it is not removable, it is recommended that the monitor be replaced or serviced at a local TV or computer repair shop.

If the monitor is receiving power, check the LED status light.

If the light is orange or flashing ensure that the monitor is not in a suspend mode by moving the mouse or pressing a key on the keyboard. If the computer does not get a display by moving the mouse or touching the keyboard, turn off the computer and monitor and reconnect the data cable from the back of the computer, and if removable, the back of the monitor. Turn the computer back on; if you still encounter the same issue, continue reading through the other possibilities.

Monitor settings are not correct

Verify the brightness and contrast is turned up or adjust the brightness and contrast. If adjusting the brightness or contrast has no affect on the monitor continue reading through the other possibilities.

No POST

Does the computer beep when it is powered on or does it appear that the computer has activity? If the computer does not beep or beeps abnormally the computer is experiencing a hardware issue or is exhibiting a No POST. Run through the POST troubleshooting steps to determine the failure.

Hardware Issue

If you have followed the above recommendations and are still encountering the same issue, it is likely that the computer may have either a bad video card or monitor. The best method of determining this is to do one or both of the following:

• Disconnect your monitor and connect it to another computer. This can be a friend or family's computer or it can be taken to a service center.
• Borrow a computer monitor and connect it to your computer. This will not harm the other computer monitor in any way.

If your monitor works on another computer it is safe to assume that the video card or potentially the motherboard within the computer is bad.

Windows error "Data or no disk loaded" with audio CD Bad or non audio CD is inserted Windows error "Data or no disk loaded" with audio CD Bad or non audio CD is inserted

 

Make sure the CD you have currently in the computer is not bad or being misread by the computer by inserting another known good audio CD into the computer.

If another audio CD works it is likely either that the CD is dirty or may be an enhanced CD incompatible with the CD Audio player. Steps on properly cleaning a CD can be found on our cleaning page.

MCI CD audio driver not installed or is corrupt

If no audio CD is working in the computer but other CDs work fine, it is likely that the MCI CD audio driver is not installed or is corrupt on the computer.

• CD-ROM not working in Windows 9x, 2000, or XP.

To reinstall or install the MCI CD audio drivers follow the steps below:

1. Click Start, Settings, Control Panel
2. Double-click on Multimedia
3. Click the Advanced tab or Device tab.
4. Double-click Media Control Devices.
5. Double-click CD Audio Device (Media Control).
6. If this device is present and no audio CDs are working, click remove on the general tab in CD Audio Device (Media Control) properties.
7. Close out of all open Windows to get back to the Control panel
8. In Control panel double-click Add New Hardware.
9. Click Next, select No, click Next -- In the box listing the available hardware, select Sound Video and Game controllers and click Next.
10. In the Manufacturers box select Microsoft MCI.
11. In the Models box select CD Audio Device (Media Control).
12. Click Next and Finish.
13. Once Windows has completed the installation of the new device, reboot the computer.

What should I do when a computer freezes?

 

This document contains recommendations on what to do if the computer freezes or dead locks. If your computer has stopped responding, follow the steps below to attempt to get the computer to unfreeze.

Tip: If you are concerned about an important document that hasn't been saved, the program you are using may have an AutoSave feature, and you may be able to recover a recent version of the document after rebooting.

Note: If your program does not have an AutoSave feature or the ability to recover a recent version of a document, you may lose all unsaved work due to a freeze or dead lock. It is important to save your work often to minimize or prevent this possibility.

Give the computer some time

Wait. Give the computer a few minutes to process. Sometimes a computer may appear to be froze, but it is really just slow or busy processing a complex task.

Is the computer dead locked?

See if the computer can respond to anything by pressing the Caps Lock key on the keyboard and watching the Caps Lock led (light) to see if it turns off and on. If the computer can turn on and off Caps Lock, continue to the next step. If nothing happens, the computer is dead locked, and you must reboot the computer.

End Task the Not Responding program

If the Caps Lock can turn off and on, Windows is still working, but another program may not be responding and causing the computer to freeze. Press Ctrl + Alt + Del to open the Windows Task Manager. If the Task Manager can open, highlight the program not responding and choose End Task, which should unfreeze the computer.

Note: It could still take ten to twenty seconds for the unresponsive program to be terminated after you choose End Task.

Reboot a frozen computer

If none of the above steps helped, you must reboot the computer. To reboot a frozen computer, press and hold down the power button until the computer turns off. Once the computer is off, wait a few seconds, then turn the computer back on and let it start as normal.

Note: During the computer startup process, you may see a screen asking if you want to start the computer in Safe Mode or Start Windows Normally. Choose the Start Windows Normally option and see if Windows starts up correctly, without error.

Resolve Hardware or Device Driver issue

If after trying all of the above there may be defective hardware or a device driver is not working correctly. A defective hard drive, stick of RAM, video card, or other piece of hardware can cause a computer to freeze. A device driver can also cause a computer to freeze if it is out of date, conflicting with another driver, or just not working properly.

If you determine that a defective piece of hardware is causing the freezes, you should replace the hardware right away, to prevent further damage to the computer. If a device driver is at fault, you can try to download the latest driver from the manufacturer's website and install it before the computer freezes, or use another computer to download the driver and try installing the driver on your computer.

If you are unable to install the latest driver before the computer freezes, another option is to start the computer in Safe Mode. Once in Safe Mode, you can access Device Manager and uninstall the hardware device corresponding to the device driver that is not working correctly. Then, restart the computer and load into Windows normally. Windows should detect the hardware that you uninstalled and try to reinstall the device driver. This process may be enough to fix the issue and stop further freezes from occurring. You can also try installing the latest driver at this point, to make sure your computer is up-to-date for that device driver.

You can also try accessing the computer BIOS and disabling any hardware that is working properly, to see if that stops the freezes from occurring. However, you should still replace that hardware, as you may not be able to use your computer fully if the hardware remains disabled.

Take PC to Repair Shop

If none of the above options work or are possible to try, we recommend you take your computer to a computer repair shop and allow a computer technician to diagnose and fix the problem.

Not a valid Win32 application

File is corrupt, bad, or missing

If the file or program you're attempting to run is corrupt or missing, Windows will be unable to execute the file properly and sometimes generate this error message.

Download files

If you downloaded this file and verified it is complete and compatible with your version of Windows, delete the file and try downloading and running it again. It's possible during the download that the file became corrupted.

Finally, if the second download does not work, try downloading the file from a different webpage. The person or company maintaining the website mistakenly uploaded a corrupt version of the file you are attempting download.

Installing a program from a CD or other disk

If you're attempting to install a program and are getting this error, verify that the CD is clean. If the CD is dirty or bad, you could get this error during the install or after the program has been installed because it was not copied properly onto the computer.

Running a program from the computer

If you're running the program from a shortcut on the computer, verify that the program is still on the computer. In some cases if the program is no longer installed on the computer you may get this error.

If the hard drive is corrupted or bad it can also cause working programs to fail either because not all the data can be read from the hard drive or because the program has become corrupted while on the drive. Run scandisk and defrag on the hard drive to check for any potential errors.

Long file name issue

Make sure the program or file you're attempting to run does not contain the same name as the long file name directory it is contained in. For example, executing a file named "program" in the "program files" directory can cause errors in some versions of Windows.

Additionally, if you're attempting to install a program and after the install the program does not work, you may also want to try installing the program in a different directory.

Bad file

Any file can be changed or renamed to be a .exe file. If you're downloading the file, make sure the file is supposed to be a .exe file and that it's not being changed. If you're attempting to create a .exe, file make sure you're compiling the file for Windows and never just rename a file to a .exe file. For example, renaming a .bat file to a .exe file will not make the file an executable file. For a file to become an executable file it needs to either be compiled or converted through a software program designed to convert the file.

File is not designed for your version of Windows

If you're trying to run a program that is not designed for your version of Windows you may get this error. Although many older programs designed to work in older versions of Windows will work with new versions of Windows, unfortunately, not all programs will work.

• If the program is an older MS-DOS program or early Windows program you may get this error.
• If the program is designed for a 64-bit version of Windows and you're running it in a 32-bit version of Windows, it will not work and generate this error.

Getting old MS-DOS games to run in Windows.

File is a virus, worm, or other malware file

This error can be generated by a file that is a virus, worm, Trojan, or other malware file. Often, this will be caused because the virus scanner installed in the computer will not allow the file to be installed or run. Try scanning the file to verify it is not a virus or infected.

If the file has been checked and is clean, it is still possible that the virus protection program or another program installed on the computer is causing issues during the install or execution of the program. Boot the computer into Safe Mode and try running the program; booting the computer into Safe Mode makes sure nothing is running in the background that could be causing this issue.

Hardware incompatibility

If you're getting this error during the installation of a program it's also possible that the CD-ROM drive or the drive you're installing the program from is not compatible with Windows or has drivers that are not compatible with Windows.