How to Reset CMOS – Recover The Default BIOS Settings
When everything is going according to the norm, most people do not even open their BIOS settings. Overclockers often live within the BIOS, and when their device fails to boot, they often reset the CMOS to recover the default settings and values.
For the regular user, knowing how to do a CMOS reset is not essential, but it can be helpful if their computer fails to boot. There are various ways to go about it, but firstly, it is important to understand what a CMOS is and why resetting it is one of the go-to solutions for boot failures.
CMOS – A Small Memory Circuit
CMOS stands for complementary metal-oxide semiconductor, which is a description of a MOSFET fabrication process. They are often used in integrated circuits, mostly due to their extremely low power usage. In a PC, they are powered by 3V batteries, their lifetime being between 5 to 10 years, depending on the usage and the environment.
The CMOS is used to store the basic input/output system, or BIOS, which holds the necessary data for the computer to recognize the components and communicate with them. It is battery-powered to preserve the BIOS settings when the computer has no power.
Why Reset a CMOS
A CMOS reset can be warranted by many situations. The most common one is a technical difficulty during the boot process. The system does not get to the operating system, thus resetting the BIOS settings to default is recommended. This may clear any and all settings which were at that moment having a negative enough impact for the computer not to boot.
An example would be a gaming motherboard, with overclocked memory and the CPU, but unable to sustain the necessary voltage due to overheating of the voltage regulator module or VRM.
There are a plethora of other issues that can be solved with a very simple hard reset of a CMOS.
How to Reset CMOS – The Simplest Ways
There are a couple of ways to reset a CMOS, the most common and recommended one being the jumper method. Other ways of resetting a CMOS are the battery and a specific CMOS reset button, as well a software reset, through the BIOS.
NOTE: All motherboards have a software way of resetting the CMOS, located in the BIOS settings. It is labeled either Reset BIOS or Reset CMOS or Load Default Values. If entering the BIOS is unavailable, then the following hardware methods should be considered.
How to do a CMOS Reset with a Jumper
This has been a standard method of resetting a CMOS and it works most of the time. The jumper method involves locating the 3-pin connector which is labeled CMOS or CLR C or anything along the lines, which should be in the motherboard manual.
Its location is often very close to the CMOS battery, which is a button battery. It can easily be spotted if not blocked by other components such as a large, 3.5 slot graphics card.
The 3-pin connector often has a jumper on it, covering pins 1 and 2, leaving pin 3 visible. The computer should be powered off before the next step. Taking the jumper off and placing it over pins 2 and 3 will clear the CMOS. Waiting between 1 and 5 minutes is recommended before placing the jumper back to its default position.
It is worth noting that some motherboards do not come equipped with a jumper, while still having the CMOS pins. Some motherboards have a 2-pin CMOS reset, but no jumper. Using other conductive metal is recommended in this case. If that is not available, there are other methods.
How to reset CMOS Battery – The Classic Off-On
Battery removal is one of the simplest ways of resetting a device Similarly, by removing a CMOS battery, the BIOS settings will reset. Some batteries are secured, so removing them might take some agility. Before removing the battery, however, the device should be OFF and the power cord should be removed.
Take note of the battery’s positive and negative sides, so that it can be returned properly.
Once more, waiting 1 to 5 minutes is recommended in order for the capacitors to be emptied and the memory completely drained of power. Alternatively, pressing the power button can drain the battery in seconds with the cord out.
Resetting a CMOS with a Dedicated Button
Some motherboards, often more expensive ones, whether gaming motherboards, high-quality ITX motherboards or professional-oriented motherboards, have dedicated clear CMOS buttons. Depending on the board, its revision and maker, the button can either be located on the board itself, either at the top or bottom or outside, with the rest of the I/O.
Pressing this button will clear the CMOS, which is actually the simplest method to do it if such a button is available.
How to Reset CMOS ASUS
ASUS motherboards can be reset by placing the jumper on the necessary jumper pins, either 2 and 3, or just 2 in case the motherboard does not come equipped with the 3-pin connector. If a jumper is not available, any conductive metal will do, like a screwdriver.
Higher quality ROG boards have dedicated buttons and the battery method should work for all boards.
How to Reset CMOS MSI
MSI motherboards can also be reset using the jumper method, whether the actual jumper or any other conductive material. Battery removal will work with MSI boards, just like any other board.
Higher-end boards, like the MEG series, should have a CMOS reset button, usually just below the motherboard chipset.
How to Reset CMOS ASRock
Most newer ASRock motherboards have a 2-pin connector which requires a simple short. Most of them come with the jumper in the box. Battery removal will reset the CMOS, provided that the computer has no other power.
More expensive boards from the Creator, Taichi and AQUA series will have dedicated CMOS reset buttons.
All of these manufacturers have a software way of resetting the CMOS, located in the BIOS settings. This option is, however, often unavailable when boot failures occur.
Conclusion and Summary
The CMOS is a battery-powered memory chip located on motherboards, used to store BIOS settings. Resetting the CMOS is recommended when a personal computer runs into boot issues or other issues with corrupted BIOS values.
Resetting can be done in four different ways, using the reset option in the BIOS settings, using a jumper to reset it, taking out the battery while the computer has no power and if available, using the CMOS clear or reset button. This will reset the BIOS to default, factory values. This should help with troubleshooting, or it can be a solution on its own.
SSD Vs HDD – Understanding SSD and HDD Nuances
Modern computers, laptops and even smartphones make use of various storage technologies, most of which can be labeled as a solid-state drive. It is assumed that SSDs are faster and better, but nothing is without trade-offs, particularly storage technology. Hard disk drives have their place, in both professional and consumer applications. What is often considered […]
How Long Should a PSU Last?
If you’re building a PC for gaming, the Power Supply Unit should be picked with utmost consideration, and not be kept an afterthought. The PSU is responsible for converting mains AC voltage to DC for your computer’s internal systems, and grounds the system. PSUs from most mainstream vendors are high quality and will easily accompany […]
How To Overclock GPU
GPU overclocking is easier than ever. All you need is a couple of apps, some free time, and a bit of patience until you find a safe, daily driver OC value. Below you’ll find a list of resources needed to get extra performance from your graphics card as well as a detailed explanation on how […]
How To Overclock a CPU
Glory days of CPU overclocking are long gone. Back in the day, you could get a completely new CPU simply by increasing the clock of your current processor. These days, both AMD and Intel push their CPUs to limits with dynamic boost features so there’s not a lot you can do to get extra performance. […]
What is Anti-aliasing? Is it important?
What is Anti-aliasing? Since graphics are made out entirely of pixels, which as we all know are tiny little squares, it’s only given that you’ll be seeing jagged edges on images. This staircase effect is what you call ‘aliasing’. Using that definition of the word ‘aliasing’, you can probably guess what ‘anti-aliasing’ entails. To put […]
What is GPU Scaling and Should You Use It?
GPU scaling is a feature that you can use to play older titles on modern displays while having a better experience. In this article, we are going to answer the question; what is GPU scaling and should you use it? What is GPU Scaling? GPU scaling is a feature that adjusts the aspect ratio of […]