No display after CMOS and BIOS reset. No display after CMOS and BIOS reset Reset CMOS memory settings
The following are instructions for performing BIOS reset, CMOS memory reset, and BIOS password reset.
Why you might need to reset your CMOS or BIOS
Information stored in the BIOS, called ESCD (Enhanced System Configuration Data), is sometimes corrupted due to various situations, such as power outages, incorrect user settings, hardware incompatibility due to a particular setting, or No POST or No video signal. In such cases, it is sometimes necessary to reset the BIOS or CMOS memory to factory defaults. In other circumstances, it may be necessary to clear the NVRAM.
Attention! When it changes bIOS settings be careful. The BIOS interface is designed for advanced users. Incorrect operation of the settings can lead to errors when starting the computer and loss of data.
2. Reset BIOS to default settings using the reset to default option
If the system can POST.
Reboot your computer. Click on Start, Completion of work and.
On the Dell boot screen, click F2 to enter the BIOS. After recognizing the command, the system settings login window will appear. Some models may use other keys. The key will be displayed during the boot process. For most Dell laptops and desktops, the key is F2.
After booting, depending on the version and type of BIOS, you can restore the default settings using the key F9 to load default options (shown as an option at the bottom of the screen), keyboard shortcuts Alt + F or the Load Defaults button on the screen to load the factory defaults.
Press the key Esc on the keyboard and select Save and exit or press the button again Log off depending on the version installed.
Press the key Enter to save all changes and exit the BIOS screen. Wait for the system to reboot to complete the BIOS reset.
Note... This operation is different from clearing CMOS / NVRAM and only returns the system to factory defaults, but does NOT clear the ESCD table.
3. Procedure for clearing BIOS, CMOS, or NVRAM using a jumper on the system board (desktop only)
Clearing NVRAM and ESCD Parameters
If you need to clear the ESCD in NVRAM, you can perform the action on the RTCRST (Real Time Clock Reset) jumper on the system board. Once the jumper is set correctly and power is applied, the system BIOS will be reset.
RTCRST - Clears NVRAM. NVRAM will be cleared when the jumper is closed (the password bridge (PSWD) jumper can be used). For proper cleaning, you need to supply power to the computer (it is not necessary to turn on the computer) for about 10 seconds with the jumper closed.
After contacts 1-2 are closed, NVRAM will be cleared and all ESCD settings will be reset
Note. You can use the above RTCRST jumper procedure to attempt recovery from no POST and no video situations.
Clearing CMOS Memory Settings
Turn off your computer and unplug the power cord.
Remove the computer cover.
PSWD).
Remove the 2-pin jumper.
Locate the 2-pin CMOS jumper ( RTCRST).
Move the 2-pin jumper connector from the password jumper to the pins in the CMOS jumper.
Power on the computer and wait 10 seconds to clear CMOS memory.
Move the 2-pin jumper connector back to the password pins.
Note. The location of the RTCRST jumper will vary by platform and form factor. For getting additional information see manuals for jumper locations maintenance systems at:
Figure: 1... Common Jumper Locations on Desktop Boards
4. Procedure for clearing BIOS, CMOS and NVRAM by removing and reinstalling the CMOS battery
This is another method that can be used to reset the system BIOS by simply removing the CMOS battery (coin cell) and powering off the system. This is usually done when the jumpers cannot be accessed on desktop systems or when using a laptop.
Note... Applies to desktop PCs and some portable systems... However, on laptop computers, access to the coin cell battery requires opening the cover on the bottom or removing the keyboard. This is not possible on all laptops. To find out if this method can be performed on your laptop, see the system maintenance manuals at.
Disconnect your computer from external power supply; on the laptop, remove the main battery.
Remove the computer cover and locate the CMOS battery (coin cell) (Figure 2 for a desktop PC or Figure 3 for a laptop)
Remove or disconnect the coin-cell battery
Press and hold the power button for at least 10 seconds to drain any residual power from the system
Reinsert or connect the coin-cell battery
Assemble the block and make sure it works
When you turn on the system, a warning will be displayed that the date and time have not been set, which indicates successful execution system reset
Figure: 2... Coin-cell battery desktop computer (next to PCI-E slots)
Figure: 3... Coin-cell battery on a laptop
5. Method of clearing BIOS passwords on desktop systems only
In addition to the RTCRST jumper, most desktop systems have a password enable jumper.
PSWD - enable password. The system password will be cleared and disabled when the system is started after removing this jumper. Closing the jumper enables the password.
Note... A password jumper must be installed on the password jumper pins in order to enable the password function.
Remove the computer cover.
Locate the 2-pin password protection connector ( PSWD).
Remove the 2-pin jumper wire and set it aside.
Replace the computer cover.
Plug in your keyboard and mouse, then plug your computer and monitor into electrical outlets and turn them on.
After loading operating system turn off your computer.
Disconnect the keyboard and mouse, and then unplug the computer and monitor from their electrical outlets.
Press the power button on the computer to ground the system board.
Remove the computer cover.
Install a 2-pin jumper wire over the password protection connector pins ( PSWD) on the system board.
Connect your computer and devices to electrical outlets, and then turn them on.
I have a very strange problem here, sorry for such a specific case, but I'm not sure what to do at this point.
So this is for context. I do not think that it is related to the problem: I had this problem which was causing the problems arising from windows updates (Windows 10). Could not find it because the interim fix was "do not shutdown the system".
Here is the real problem: I had break at power supply ... But the only thing what went wrong, I couldn't boot into Windows. Failed to load in safe mode, but might boot into the console (I might go to "fix windows troubles EUFI "). This may be due to the above problem, possibly due to power being disconnected from. So, after studying the first one, I thought I would like to point out the problem with the BIOS. Looked and I turned off all the power of the PC, and held the power button in other words, a flea leak.
Seems pretty harmless but now my computer won't show at all ... Disconnecting my graphics card tried the integrated graphics. Nothing yet. These are not my monitors because they were working before I did it (after turning off the power). Then I took out the battery for 10 minutes by holding the power button down for 30 seconds (when disconnected). Nothing yet. But it does post messages (at least the motherboard LEDs turn on, the fans spin, everything is as you think it should be). Cabinet speaker makes a barely audible ticking sound (not a complete beep). I just installed it after getting the problem, so I don't know if the ticking is normalized.
Don't assume my specs are relevant, got a custom PC. Will post specifications if requested.
So, I am not asking for any help in windows problem, I'll figure it out later;). I just wanted to know what to get back?
TLDR : Not displayed at boot. POST, no apparent hardware issues. A quick list of things that lead to the problem:
- Power error caused by (presumably unrelated) Windows issue
- Tried to fix it by holding the power button off (power flea leak ... it resets the BIOS, doesn't it?)
List of things I tried to fix:
- Took out the CMOS battery, pressed the power button down (while disconnected)
- Diagnosed and in working order: monitor, video card, power supply. The motherboard LEDs turn on.
I am at a loss, any help would be greatly appreciated, thanks!
EDIT: Added hull dynamics info. It is ticking.
How to reset BIOS - for sure, this question has repeatedly risen by the edge for many users personal computer... A procedure such as resetting the BIOS settings can be extremely useful in cases when the computer is not helped by a reboot and, as it seems, cannot be revived by the users, and the only way to restore the PC's performance is to visit a repair shop. Since resetting the BIOS returns the factory default settings, this method often helps to solve problems associated with a malfunctioning PC.
You may need to reset BIOS settings for various reasons. For example, it may happen that you experimented with computer hardware as part of a CPU overclocking exercise, and as a result, your computer simply stopped booting. Or you need to reset the password that prevents you from entering the BIOS. In short, the reasons can be different. The methods for resetting the BIOS can also differ, and not every method can be applied in every situation. But it’s better about everything in order.
All methods of resetting the BIOS can be divided into two main categories: hardware and software. The most famous methods at the moment include the following:
- Reset BIOS to default settings using BIOS Setup.
- Reset by setting special jumpers on the system board.
- Reset by removing the battery motherboard.
- Reset by closing certain contacts of the BIOS chip.
- Reset by programming ports.
Let's consider these options in more detail.
Resetting BIOS to default settings using BIOS Setup
The easiest way to perform the BIOS reset procedure is to start with this software method. To implement it, it is enough to enter Setup (as a rule, by pressing the Delete key on the keyboard when starting the computer), find the appropriate section, select the desired option and restart the computer. After a reboot occurs, the BIOS will revert to factory defaults. There is an option to load BIOS defaults in almost every bIOS version... It's usually called Load Defaults or something like that.
Everything seems to be simple, but there are some limitations. The thing is that it will be difficult for you to apply this method if you cannot enter BIOS Setup - for example, when your computer does not boot at all. A similar situation occurs when an unknown password prevents entering Setup or continuing to work with the computer after boot. Thus, the functional usefulness of the described method is limited.
Resetting the BIOS by installing special jumpers (jumpers) on the system board
Naturally, many motherboard manufacturers provided for the possibility that the user would not be able to clear the BIOS memory using Setup and load the standard factory settings in a similar way. Therefore, the board designs have built-in solutions that allow hardware resetting of BIOS settings.
Most often, a special jumper can be used for this purpose. Of course, find a small jumper on a large motherboard not always easy. Therefore, it is usually best to look at your motherboard manual to find it.
If you do not have a manual with you, then you should remember that quite often this jumper is designated on the motherboard as Clear CMOS (and therefore given type jumper is often referred to as Clear CMOS).
Clear CMOS jumper on motherboard
In addition, the jumper is most often found near the battery that powers the CMOS memory. However, this rule is not always followed, so it is safer to use the motherboard circuit to find the jumper.
Usually, closing the Clear CMOS jumper is sufficient to clear the CMOS memory. For reliability it is worth keeping the jumper closed for a while. Typically, after a few seconds, the BIOS memory is erased, and after that you can turn on the computer again.
We hope that all readers know the following principle, but still recall it once again: all jumper setting operations must be carried out on a computer completely disconnected from the network, otherwise the results can be disastrous for the motherboard.
Resetting the BIOS by removing the CMOS battery from its socket
If there is no corresponding jumper on the motherboard (or you could not find it), but there is a CMOS battery on the board, then you can try resetting the BIOS memory in the following way - just pull the battery out of its slot. However, this method is not always as effective as it might seem at first glance. The fact is that CMOS memory usually does not require a lot of power to work and therefore BIOS data located in this type of memory can remain in it for a long time even in the absence of power. Therefore, in order to make sure that you managed to completely clear the BIOS memory, you need to hold system unit without a battery for a while. Usually, after a day, the CMOS memory is completely cleared, although very often a shorter period of time may be sufficient for this.
Appearance CMOS batteries
A CMOS battery is usually quite easy to find on a motherboard - it is usually made of shiny metal, and its surface is in the shape of a circle with a diameter of 1 cm. Removing the battery is also quite simple - just press the special latch that holds the battery in the socket.
As with the jumper operation, the CMOS battery can only be removed when the computer is completely disconnected from the mains.
However, it should be borne in mind that the battery is not always removable. Quite often, especially on a laptop, it is simply impossible to remove the battery without damaging the motherboard. In this case, the only way out for the user is often to go to the service center.
Other ways to reset the BIOS
If none of the above methods helped you, and you do not know how to clear the BIOS memory, then in some cases you can try other methods. However, they are not as reliable and you should use them only at your own risk.
First of all, it is worth noting that such a frequently mentioned BIOS reset method, like closing the contacts of the BIOS battery, can hardly help you. Moreover, if you apply it, then it will be fraught with failure of the motherboard.
However, for some BIOS chips, a positive result is sometimes brought by the closure of certain pins of these chips. Below we provide a list of the corresponding microcircuits and the procedures that must be performed with them to reset the BIOS:
- Р82С206 Chip - closure of contacts number 12 and 32 (or 74 and 75).
- F82C206 Chip - closure of contacts 3 and 26.
- Dallas DS1287A, DS12887A, Benchmarq bq3287AMT - closure of contacts 12 and 21.
- Motorola MC126818AP, Hitachi HD146818AP, Samsung KS82C6818A - closure of contacts 12 and 24 (it is also possible to pull the microcircuit out of the socket).
- Dallas DS12885S, Benchmarq bq3258S - closure of contacts 12 and 24 (or 12 and 20).
When performing actions to close the contacts of microcircuits, you should adhere to a few simple rules. First of all, it is worth remembering that all operations with microcircuits should be carried out only when the power of the computer motherboard is turned off! In addition, often simply closing the contacts may not be enough to reset the BIOS, so it is best to keep the contacts closed for a few seconds.
In addition to hardware resetting the BIOS, as well as resetting using the Setup program option, there are also purely software methods based on writing a certain set of data to the computer ports. Firstly, special utilities can be used for this purpose. But if you do not trust the programs downloaded from the Internet, then you can create a similar program yourself. The easiest way to do this is to use the Debug utility included with MS Windows. To carry out the operation to clear the BIOS from AMI or AWARD manufacturers, just run the Run program and enter the following set of commands:
After entering these commands, a computer restart is required.
Features of reset BIOS for laptop
How to reset BIOS - this question arises no less often for users working on a laptop than for those users who use a desktop PC for work. However, on a laptop, this operation is usually somewhat more difficult. In many cases, the same methods can be used on a laptop as on a desktop PC. However, often on a laptop, the user may encounter enhanced BIOS data protection, especially on a top-class laptop. In this case, to perform a BIOS reset operation on a laptop, it is best to contact a specialist.
Conclusion
Anyone might find it helpful to know how to reset BIOS settings. If your computer shows no signs of life, malfunctions, or you cannot boot it because you do not know the password, then you should not despair. Resetting the BIOS content to factory settings in most cases will restore the computer's performance.
There are many ways to reset BIOS settings, and the most reliable and universal of them are hardware methods, such as installing jumpers on the motherboard or removing the CMOS battery.
The abbreviation CMOS stands for Complementary Metal-Oxide-Semiconductor. It is a tiny memory device that is used to store BIOS or UEFI settings. These settings are responsible for how your computer will boot, various low-level settings for the processor, memory, buses, and overclocking.
You may need to reset the CMOS memory after an unsuccessful attempt to overclock the computer or when the computer simply does not boot as a result of something you have done wrong in the BIOS settings. Clearing the CMOS will simply return all settings to their default values \u200b\u200band everything will work. If you assembled your computer yourself, then you know exactly how to do it, but for people who bought their device, such a task can be difficult. In this article, we will look at how to reset computer CMOS memory.
HOW DOES CMOS MEMORY WORK?
The CMOS memory that stores BIOS settings is volatile. It is powered by a special battery built into the computer's motherboard. This was not done in vain. BIOS settings by default are written to non-volatile memory and are never changed. All changes made by the user are saved in volatile memory.
The correctness of these settings is very important, because it depends on them whether the computer boots up or not, and as a result you can change them or not. And if the user makes any mistake in the settings, it is enough to simply turn off the memory and the settings will return to the default value. It's simple. Now let's see how to do it.
HOW TO RESET THE SMOS MEMORY VIA RESET?
If your computer has a Reset button, you can reset CMOS settings using it. It can be used not only to restart the computer, but also for this. Just follow these steps:
- Turn off your computer;
- Unplug the computer from the power outlet, you can unplug the power cord from the wall outlet or the power supply connector on the back of the computer;
- Find the Reset or Clear button near power buttons on the front of the computer;
- Hold the button and hold it down for five to ten seconds, then release. If the button is very small, you will need to use a needle or pen;
- Connect your computer to the network and start.
Basically, that's all. This set of actions is enough to reset the settings in most cases. You can also start the BIOS, for this you need to press Del or F2 before starting the boot and select the option "Load Optimized Defaults" this would be ideal.
RESET CMOS BY BUTTON ON MOTHERBOARD
Most modern motherboards have special button for clear CMOS... It can be accessed after you open the computer case cover. It can be called CLR, CLEAR, or RESET. The procedure is almost the same:
- Turn off your computer;
- Press the power button several times to discharge the capacitors on the motherboard;
- Unplug the computer from the power outlet or remove the power supply cable;
- Find the button on the motherboard. If you cannot find it, please refer to the manual for your board model. AT different models they are located differently;
- Hold the button and do not release it for five to ten seconds;
RESETTING THE CMOS BY REMOVING THE BATTERY
If your board does not have Reset buttons, and this situation very often happens with laptops, then you just have to remove the CMOS battery. This battery powers the memory when the computer is not connected to the network. Removing the battery is equivalent to forcibly erasing the memory. How to reset cmos on laptop:
- Turn off your computer;
- Disconnect the computer from the power supply;
- Press the power button several times to discharge the capacitors;
- Find the battery on the motherboard. This is usually a coin-sized CR2032 battery. You can find it near the PCI Express slots;
- Remove the battery, you may need to press a sharp object on the retaining element or pull it out from under the latch. Proceed carefully, do not break the structure;
- Wait a few minutes, and then insert the battery back, the same side as it was installed before;
- Plug in the power and turn on the computer.
JUMPER CLEAR CMOS
Among other things, the motherboard has a special jumper with which you can reset the settings:
- Turn off your computer;
- Disconnect it from the power supply;
- Press the power button several times;
- Open the computer case and locate the CMOS reset pins on the board. Usually, these are two or three pins put together and signed by CLEAR CMOS or CLRPWD;
- For a three-pin configuration, move the plastic jumper so that the center contact is closed with the one from which it was previously disconnected. With two-pin, just disconnect the pins.
- Wait a few minutes and then return the switch to the position it was in before;
- Turn on your computer.
CONCLUSIONS
In this article, we looked at how to reset the cmos on the motherboard, as well as using the Reset button on the case. If you forget your password or mess up the BIOS configuration, you just need to restore everything. Hope this information was helpful to you. If you have any questions, ask in the comments!
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