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How to Overclock a CPU: Things You Need to Know to Get Started

how to overclock a cpu

Overclocking – a word so familiar to anyone who has ever dealt with computers, but still pretty mystic for many. The truth is that it shouldn’t be like that. Although it might sound confusing at the first glance, overclocking is actually a straightforward process.

You don’t have to be a rocket scientist or anything close to that to achieve it. All you need is to be patients and willing to go through the number of tests and adjustments and find the perfect settings for your computer in order to increase its capabilities.

Why Overclock a CPU?

Many people don’t really have a need for overclocking, but on the other hand, there are so many of them who would find it very beneficial. It could be in order to give their aging hardware a few more months, if not years of work, or to upgrade their brand new rig to work faster and get better performance for lower cost. Reasons are various, but the advantages themselves can be summed up into a few things. If you have ever asked yourself: Why should I overclock my CPU? These are the arguments:

  • Faster system run
  • Drastic improvement in system performance of the tweaked components
  • Run of a heavy software without glitches
  • The smooth flow of the apps or the system

Of course, this path also brings some possible problems on the way and it must be taken into account that playing with your hardware can prove to be fatal for it – especially if you have no clue what are you doing. Therefore, before anything else, think about the possible consequences. Finally, if you decide for overclocking, prepare yourself for possible failures of your components.

That doesn’t mean that crashes will happen, but be aware that there is a possibility. If you follow one simple rule – to go slow with your twitching – chances for a hardware failure rapidly decrease. Therefore, be patient. Do one thing at a time and there is a huge likelihood that you will avoid any problems.


Overclocking itself doesn’t necessarily require for any additional software (if you decide for a BIOS twitch), but checking of your computer’s stability does. The processes of monitoring, stress testing, etc. require certain software solutions that will make your work possible, and the overall finding of the perfect setup much easier.

Some of the best options for temperature monitoring are the following:

  • OpenHardwareMonitor supports the majority of today’s monitoring chips and it offers detailed information about the CPU and GPU temperatures of your configuration.
  • Real Temp is a free program designed for monitoring of the Intel CPU temperatures. It is simple and easy to use and it offers all the temperature information you need. Unfortunately, it is not compatible with AMD processors.

For stress testing, you can choose one of these:

  • LinX is an excellent CPU benchmark app that will check your system stability. It can detect problems with your hardware and it offers a great stress testing program that will determine your tweaked CPU stability.
  • Prime95 is one of the best free stress testing tools that will push your rig to the maximum and offer you an answer to the question of whether your overclocking setup is stable enough or not.

For both temperature monitoring and stress testing, try this one:

  • AIDA64 is an amazing diagnostics, benchmarking, stress testing and overall monitoring software that has multiple uses and can be marked as great CPU overclocking software, although that is not its primary purpose. There are versions for numerous operating systems such as Windows, iOS, Android, Chrome OS, etc. AIDA64 provides all the needed information, including the data about the components themselves. The only downside is that it is not free, but there is a free trial period.

A great option for checking overclocking settings can be this one:

  • CPU-Z is an overclocking must-have. Although it is not important for the overclocking process itself, it offers plenty of information such as processor name, codenames, number details, memory types, sizes, real-time core frequencies and memory frequencies. It identifies processes, cache levels, packages, and much more, and it can even test the performance of your mainboard and chipset. It’s a great overall software that will bring you all the information you might need.

Also, there are all-in-one software utilities that allow you to overclock your CPU, stress test, monitor and much more, all with one tuning utility. Both Intel and AMD have this type of software and it’s important to note that they’re free.

Therefore, if you are into an easier overclocking, you can use one of the following:

  • Intel Extreme Tuning Utility & Desktop Control Center is a tuning software specifically designed for Intel processors (of course, only those with K mark) and Windows OS. This utility offers a great set of features that allow for a lot of twitching of both your Intel CPU and motherboard.
  • AMD Ryzen Master is an excellent CPU overclocking software designed only for Ryzen processors. It allows you to personalize your CPU performance by providing the detailed control over every part of your chip and tuning of your computer to the maximum.
  • AMD OverDrive is an AMD utility intended for overclocking of all modern or relatively modern AMD processors other than the Ryzen series. This software maximizes the capabilities and flexibility of the configuration allowing for an automatic or manual tuning of the system.

… but be aware that the better stability of the system and safety of your hardware is achieved through BIOS twitching. For that reason, BIOS is certainly a better option, although all-in one-software utilities are definitely faster. This guide, on the other hand, will be mostly about the BIOS twitching with mentioning of the software options.

Before the Overclocking Starts

The last thing you need when overclocking is to do it on a hardware that is already unstable, or faulty. Twitching on that kind of a system or components can be devastating and lead to even bigger damage, and that is something nobody needs.

Therefore, before the actual process of overclocking it is necessary to do some checking and testing:

  • Checking CPU stability – The best way to check if your CPU is stable enough is to stress test it. As previously mentioned, some of the best tools for that are Prime95, LinX or AIDA64, but there are many other apps that will also do the job. Therefore, if you are sure of their efficiency and reliability, feel free to use them. In this part, it is important to see how your processor reacts to maximum loads and to see if there are any BSODs, random restarts, or similar. Most people say that 10 to 15 minutes of stress testing is enough, but to be sure, feel free to “torture” you CPU for at least an hour. That won’t harm it and you will be sure that it is stable.
  • Checking core temperatures – The process of temperature monitoring should be done in both the idle mode (system has finished booting, but there are no opened apps besides the necessary ones), and when the CPU is under full load. All you need is to install one of the programs for temperature monitoring (for example OpenHardwareMonitor or Real Temp) and observe the values. To achieve your processor full load, use the previously mentioned Prime95 (or a similar software), choose “blend mode” of stress testing, and in a couple of moments, your CPU will be under full load. Wait for a couple of minutes and you will have the maximum Core temperatures.

Overclocking Itself

After all the preparations, it is time for the overclocking process itself. As previously mentioned, there are two ways to achieve it. One is through the software and other (more recommended) is through BIOS itself. This guide will present them both and it is up to you to decide which one will suit you better.

Software Overclocking

To overclock Intel processors, you can use Intel Extreme Tuning Utility & Desktop Control Center, and in case of AMD CPUs, there are AMD Ryzen Master (only for Ryzen processors), or AMD OverDrive. With all three of the utilities, you will have access to the settings that you need in order to overclock, such as power, voltage, core, and memory. They are easy to use, therefore you will have no problem achieving the best results, plus this type of overclocking doesn’t require for reboot, and because of that, the whole process should be faster.

Just have in mind that all three of these software utilities demand for constant monitoring of the temperatures in order not to fry any of the components. Therefore, as with BIOS twitching, be careful and do everything step by step. Change some of the settings and then stress-test and monitor the values. It is a longer approach, but it surely safer.

BIOS Overclocking

Although BIOS overclocking demands for more time, it is more stable and offers greater safety of the components than the software overclocking. Also, it is generally considered by enthusiasts as the only proper way of overclocking. Therefore, it doesn’t surprise that the majority of users prefer this method.

Now, let’s start.

Entering BIOS

If you have no clue how to enter BIOS, the answer is simple. Restart your PC and keep pushing Del or F2 key on your keyboard (this may vary depending on the motherboard manufacturer, but in the majority of the cases, it is one of these two keys) and you will enter Its Highness BIOS (or UEFI BIOS on newer motherboards).

Auto Overclocking

Once you’re in, you will see a whole bunch of settings and in the case of newer, more expensive motherboards, options for loading auto overclocking profiles. These profiles are usually named “Optimized CPU OC Settings” or something similar, which also depends on the manufacturer.

What’s important for these settings is that they deliver different overclocking profiles that increase computers performance, but only in a certain percentage. They will, for instance, offer an increase of the CPU speed from 3.5GHz to 4.0GHz, but for pushing you CPU over 4.8GHz, you will still have to use manual twitching.

The reason for this is safety. These profiles are generally safe and are intended mostly for modest performance improvements that will not in any way harm the hardware. Therefore, if you want a drastic increase of the CPU and overall performance, manual overclocking is still the only real option.

Manual Overclocking

When talking about this method, it must be stated that this type of overclocking is the slowest, but also the safest way of overclocking. The process itself consists of several steps:

  • Changing the multiplier
  • Testing
  • Increasing Voltages
  • Benchmarking

If it looks simple to you, have in mind that every one of these steps requires a lot of repeating, stress testing, tuning, etc. In other words, hours and hours of careful work are needed, to turn your processor into a “beast”.

Changing the multiplier

Every processor has a multiplier or a “clock ratio” that presents a speed ratio between the FSB (Frontside Bus) and the CPU. In other words, if the CPU has a multiplier of 20 and an FSB speed is 133MHz, the speed of a processor is 20x133MHz or 2.66GHz.

Exactly this gives you the answer to how to overclock CPU: by increasing the multiplier. In this case, with a processor that has a multiplier of 20 and an FSB of 133MHz, if we increase the multiplier to 28, the processor speed will increase to almost 3.72GHz. Of course, this type of increase can be devastating if done suddenly. Therefore, if the plan is to achieve something similar, you’ll have to go slowly.

First, increase the multiplier just by one to 21. Save changes, reboot and wait for Windows to boot.


After you have done that, do a set of testing. Open your temperature monitoring software such as Real Temp, then CPU-Z for checking for proper application of your settings, and in the end, open a stress testing software such as Prime95.

If you have decided for Prime95, go to “Options”> “Torture Test” and select “Blend Test”. Test for 10 to 15 minutes and if there is no problem, increase the value of the multiplier by one more and stress test again.

prime95 blend test check

This whole process should be repeated until you get one of the following scenarios:

  1. Testing shows some kind of error or your computer crashes and you get a BSOD. This means that your voltages are too low and that they need to be increased. If this scenario happens, it is time for voltage increase part.
  2. Your CPU temperature is too high. This peak value is different from CPU to CPU. Therefore, if you have an AMD CPU, Google the forums to see what other users of that processor suggest the maximum temperature for it is. In the case of Intel processors, find its declared Tmax temperature, and until your processor temp is 10 to 15 degrees below it when it is under load, you are fine. If you realize you reached the max values, it is time to finish overclocking and go to benchmarking section.

Increasing Voltages

As previously mentioned, increase your multiplier and stress testing continuously as long as you don’t end up with errors: BSOD or your CPU starts to thermal throttle. The best case scenario is to get a BSOD before the thermal limit, but that is not up to you.

If that happens and BSOD shows up first, it is time to start working with your Vcore voltage. As with multiplier, these setting are located in the BIOS and the thing you are looking for is the CPU Vcore Voltage Mode (or something similar). You need to change this setting to “fixed” and the process of voltage increase can begin.

Of course, it is always a good idea to research a bit and see what other people suggest, what stock Vcore your CPU can stand, and to look for general advice on how to overclock the CPU that you have.

The increase of voltage should be done by 0.01 volts (when you get more comfortable with overclocking, these increases will probably be done by 0.05 or 0.1 volts), after which you should save changes and try to boot your computer. If that happens, stress test your system, observe the temperature values and wait for 10-15 minutes to see if your computer is stable enough at the new target frequency. If it is, you can increase the multiplier by one again and repeat the whole process until you reach the maximum values.

If you, on the other hand, can’t boot, or the system isn’t stable enough, you need to increase voltage by another 0.01 volts, save changes, try to boot and repeat the whole process of voltage increase until you can boot up your system and successfully go through the stress testing process. Once you reach it, it is time for the multiplier part again and the whole process continues until you end up in a dead end, or in other words, reach the maximum numbers.

This is the moment when you cannot raise your CPU frequency any longer no matter how much you increase the voltage. At that moment, it is time to decrease your CPU frequency by 0.1GHz and set your Vcore voltage to the last value under which that frequency was stable. When you reach this point, it means that you are basically finished with overclocking.


The last part of the journey is also the least attractive part, and that is testing or benchmarking of your overclocked rig. How long you are going to test it is up to you, but it is essential in order to be sure you have increased the performance, but still got the configuration that is stable enough.

Whether the testing itself will last for an hour or a few of days it is up to you, just be sure to perform it.


If after reading this guide, you are still unsure about the whole overclocking process, and too worried that you will mess something up, then maybe it is a better idea not to do anything, or let someone who knows what they are doing to do it for you. On the other hand, if you are an adventurous spirit and want to play and lead your hardware to its limits, go for it.

Just be careful and do the things slowly, one at the time. Patience will pay off.

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