VCIOO: Learn More About CPU Voltage

VCIOO is a core voltage unit that the CPU uses nowadays. It is used to keep the check on voltage for the memory controller and share cache, as the memory-controlled voltage comes directly into the CPU.


Keep reading the article to find out more details!

Role of VCIOO in VID

VID stands for Voltage Indication Number. Every processor has its VID. VID is used by manufacturers of the CPU to define the maximum voltage a CPU can use. It can be confusing for users sometimes because although each CPU model has its VID, not all CPUs of the same model will need the same voltage to work properly.

How Overclocking CPU Affects Primary Core Voltage

Overclocking and voltage are interlinked with each other. When you overclock your computer, not every CPU will have the same safe voltage. Some CPUs need low voltage, while some need higher voltage to work properly. The rate without running a stress test can be difficult to identify.

Usually, it depends on silicon quality, and you can’t check it through a test run. Therefore, the manufacturers provide us with the VID at the possible lowest level to check the computer’s stability. CPU voltage will fluctuate according to the load you put on the CPU.

Everything is controlled by the Motherboard but professional gamers, they have to often overclock their computer to make it give a boost by fluctuating the CPU voltage.

Details on CPU Voltage

The CPU voltage limit can be seen in your computer’s BIOS. There are a total of three CPU voltages. 1.12500 voltage is set on the computer automatically, but it can be changed to check your CPU voltage limit in case you want to overclock or underclock a CPU.

Details on CPU Voltage

If you want to boost your CPU voltage by overclocking it, you’ll have to overclock your RAM and not depend on gentle overclocking. Overclocking RAM demands more voltage from the CPU in order to reach and stay on a high frequency. Sometimes CPUs have a higher VID than what they need to function, and to save the power, you can lower the voltage. Lowering voltage can decrease the internal temperature, which is dangerous for sensitive technologies.

To check the used CPU voltage, the following formula can be used:

The Amount of Power Used by CPU = The Amount of Heat Generated = The CPU Voltage Used

When you are not overclocking, the CPU’s core voltage level remains at a constant value. But it fluctuates when the computer is under heavy load.

How to Overclock Computers Safely

Overclocking is an extremely difficult process, therefore if you’re not careful, your computer can become unstable, or worse, it may burn. If the computer gets overheated, overclocking can do permanent damage. 

It can make your computer perform slower instead of working faster. As a result, programs may crash, and gamers may face stuttering problems while playing. In the worst-case scenario, a computer may stop booting up. This happens because of the deficiency in the voltage and the computer stops working properly.

Therefore, if you want to overclock, you have to increase the voltage level of your CPU. It is tricky because it is a guess-and-check situation for the users. You will have to check different numbers to identify the perfect level of voltage for overclocking. Please note that it is different for different computers.

How to Adjust the Computer’s Voltage?

In order to adjust the computer’s voltage, you have to access the Motherboard’s BIOS. Vscore is determined in decimal values like 1.12500. But since this is an auto-setup of your computer, it may not be the perfect voltage.

In some computer models, you’ll get a notification once you reach your voltage limit, whereas, in some models, you’ll have to keep a check on it by yourselves. So you will need to stress test before overclocking the computer to get a baseline value for the speed. We can also find the voltage limit according to the manufacturer of your CPU from a Google search.

Please note, it is easier to find the voltage limit in a gaming computer model but harder in the normal, pre-build computers. But still, some publications will show the voltage list, or you can find it in the book that comes with your computer. The values you’ll find will help to start from the very beginning, so you can get to the perfect level much faster when trying overclocking.

What to Do If the Stability Issue Wasn’t Detected

If you’re unable to find the stability issue after booting your computer, you can try either increasing or decreasing the voltage. While overclocking, find the lowest voltage rate that keeps the computer stable because the lower the voltage rate, the less heat will be produced and there will be fewer chances for overheating problems to occur. 

If you want to safely adjust the primary core voltage of your computer, you have to do it by decreasing 0.01 volts each time. This will make the CPU’s voltage decrease gradually, and you’ll be able to see the impact on a certain number. Eventually, lowering it too far will cause the system to crash.

If you reached that level that your system crashed, use even smaller volts to go back up until the system is stabilized again. Make adjustments and increase 0.001 volts each time. As you’re overclocking, you have to keep an eye on the computer’s heat temperature and analyze the impact it has on the computer.

How to Underclock Computer Safely

Some people choose to do overclocking while some choose to underclock to make their computers work best. They choose to under-volt it because it has fewer chances of overheating their CPU.

Some users opted for Turbo Boost , but that option isn’t the best to decrease temperature. While you can witness the inner temperature going down, it still isn’t effective for everyone because it can cause problems in the productivity of the computer. It can make the computer perform worse than it did before. But in case you want to make small adjustments , so it doesn’t affect your computer performance, you can opt for Turbo Boost.

How to Underclock Computer Safely

To underclock, a few starting steps are similar to that of overclocking. Start by decreasing Vcore, each time increasing 0.01 volts, and then fine-turning the amount by adjusting 0.005 volts until you get to the temperature you want.

The primary core voltage or memory-controlled voltage is something a user shouldn’t mess with or try to adjust without knowing about it. Because doing so can damage users’ computers if they are not careful with it. But for gamers, underclocking is very helpful.


1. What Is the Normal Primary Core Voltage in a Computer?

Usually, a typical core-voltage requirement ranges from 0.9V to 1.3V, and it is defined by specific performance criteria of the processor. The new core-supply voltage requirement is 3% less or more volts.

2. What Is VDroop?

VDroop means when the motherboard doesn’t supply the processor with the complete amount of voltage in the BIOS that is required to make the computer work properly. It is the difference in voltage between the BIOS settings and CPU loads to work properly.

3. What Controls VCIOO Voltage?

The motherboard controls the voltage of the CPU. If not overclocking or underclocking the computer, the motherboard handles all the core voltage required by the CPU or processor chip.

What Controls VCIOO Voltage

4. Is Vcore the Same as CPU Voltage?

Yes, they are the same. Vcore is the voltage that the CPU uses to work properly. The amount of power the CPU uses and the amount of heat that is generated are tied to the amount of voltage it draws.

5. What Voltage Is Too High for the CPU?

The CPU has a maximum voltage that it can bear, typically 1.75V is too high for any CPU over the 65nm process.


After reading this article carefully, you know what Vcore voltage is used for and the various ways you can use to fluctuate it and increase the processor’s speed of the computer. Some major points from the article are listed below to make it easier for you to remember the important topics:

  • The Vcore voltage is the primary voltage that your CPU uses to work properly.
  • Overclocking can be done to fluctuate your voltage limits in order to increase the processing speed of your computer without burning it.
  • Similarly, underclocking can be done to decrease the temperature of your computer and to lower the voltage CPU consumes.

We hope you found the information you were looking for in this article and now have a good understanding of VCIOO. 

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