Overclocking, simply stated, is the process of increasing the processing speed of a computer component beyond its factory value it was designed for. Clock speed is defined as “The operating speed of a computer or its microprocessor, defined as the rate at which it performs internal operations and expressed in cycles per second (Hertz). E.g. A computer processor running at 2 Gigahertz will carry out 2 billion instructions per second. Overclocking is commonly undertaken by technology enthusiasts who want to squeeze as much power out of their components as possible as an increase in clock speed will make your computer carry out tasks faster.
Basic Overclocking is a cheap way to increase performance without hardware upgrades. It is not without its risks though; Overclocking (if done incorrectly) can lead to long term damage or unreliable performance increases.
The most common components that Overclocking takes place on are the Central Processing Unit (CPU), Graphics Cards and Memory since these components yield the best performance increases when overclocked. We’ll be focusing here on the CPU since this is the most commonly overclocked component and a good starting point. Overclocking the CPU can make your whole system faster, boot faster, increase loading times in applications and games will be increased and frame rates can also be increased.
Before you decide to overclock you’ll need to check a few things:
- First you need to be sure that your motherboard will allow you to change settings which will allow you to overclock. Manufactures like Dell and Hp block users from tweaking these settings.
- Check your CPU temperatures at idle and when being stressed (ie undertaking a number of tasks that will tax the PC to its limit). Use a downloaded free tool such as cpu thermometer. Overclocking will increase your CPU temperature so if it is already running high then it would be dangerous to proceed. Under stress it’s not wise to exceed around 80 oC
- Download a program to test the stability of your CPU once overclocked. I recommend Orthos.
- Most warranties do not cover damage caused by Overclocking. You’re on your own if you muck up!
- Most of all you need to be a bit tech savvy and know the fundamentals of a computer system, Overclocking is an advanced technique and should not be attempted by everyone!
The CPU Clock speed is usually determined by the CPU Multiplier and the CPU FSB (Front Side Bus). The CPU Multiplier is the ratio between your CPU and the FSB on your motherboard. The FSB connects the CPU and the memory or RAM and other components on the motherboard. Increasing the FSB will increase the speed of your whole system as well as the CPU. Increasing the CPU multiplier will increase the CPU speed but it is harder to fine tune clock speeds with the multiplier since they have to be whole numbers. The principles of Overclocking go down the very technical fundamentals of how a computer system works this is why you shouldn’t undertake extreme Overclocking until you really understand what you are doing.
To demonstrate the benefits of Overclocking I have put together two benchmark scores. One before and one after Overclocking. The processor used is a “TripleCore AMD Phenom II X3 Black Edition 720, 2800 MHz (14 x 200)” It is currently running at 2.8 Ghz, has a multiplier value of 14 and the system FSB is 200. (14 x 200 = 2800) Below are a table of my results and a graph to show the improvement that has been achieved. I used a benchmark tool to test the CPU speed called “CPU Free Benchmark 2.2” Follow what I have done below as a guide only, do not copy it exactly since every CPU is different in its own ways. I accept no responsibility for any damage you may cause to your hardware.
1) I started with my control, the stock CPU speed (test no 1) the average time was about 48 seconds to complete the benchmark tests. So once I had that I could start the Overclocking. Always proceed in small steps, I decided to jump from 2.8 to 3.0 Ghz, an increase of 0.2 Ghz as this is a pretty small Overclock.
2) I conducted the tests at 3.0 Ghz twice, first time increasing the FSB to 231 and decreasing the multiplier to 13. This instantly showed improvements to the test score and no signs of system instability occurred. I then changed the multiplier back to 14 and the FSB to 215. The speed was roughly the same so I know the FSB is not bottlenecking the speed yet. I then proceeded to increase the speed further.
3) In order to demonstrate how the variation between the multiplier and the FSB work I have conducted multiple tests at 3.2 Ghz. Tests 4 & 5 & 6 were extremely similar because they had fairly low multipliers and increased FSB. Test 7 shows the bottlenecking effect come into show that is created between the CPU speed and the FSB. The multiplier was set high and the FSB left as standard but as you can see, even though the clock speed was the same throughout the 3.2 Ghz tests, the time is increased on test 7. This is why you need to get a good balance between CPU speed and FSB and later the CPU voltage.
4) Again with another 0.2 Ghz increase, the clock speed was set to 3.4 Ghz. When you start getting to higher clock speeds you will eventually need to increase the voltage to the CPU to deal with it. It will become apparent when the PC stars behaving erratically or not booting properly. The two 3.4 Ghz tests show two different voltages and how the voltage change does little to the speed of the benchmarks when it is not needed.
5) It was when the 3.6 Ghz mark was hit that problems started to arise. As you can see from test numbers 12 to 15, the PC would not boot at all . The clock speed had been set to high and the voltage needed to be increased in order to cope. Through trial and error, 1.4 volts was the magic number and boosted the speed to a whopping 3.6 Ghz, a 0.8 Ghz increase on the stock speed and cut over 10 seconds off the benchmark times. You have to be really careful when setting the voltage on your CPU or any components since upping it too much will completely kill the component, likely costing you hundreds to replace.
6) An important factor to note also is the increase in temperature once the CPU has been Overclocked. Consistently throughout the tests with more speed comes more heat, especially once the voltage has been increased. After Overclocking check your temperatures all the time and stress the computer for long periods to ensure that it will be stable. I could have gone further as I know some have reached up to 4 GHz on the same processor but I am happy with this result. Pushing it any further will start to increase temperatures much more dramatically and upping the voltage further is risky. But overall a 0.8 GHz increase is really good! You have to not get carried away with it otherwise it will go bad unless you start using special cooling equipment.
In order to start Overclocking your system you need to enter your BIOS. Check how to enter your BIOS screen but it is usually pressing the Delete key during boot up. You’ll be faced with many options and every motherboard is different. Look under advanced settings or anywhere until you find something to do with CPU settings or “Jumper Free settings” as these are the most common places to find the tools to Overclock. If it is supported it will usually describe all the options in your motherboard manual. Once you have found the right page you can start tweaking the settings until you find ones that work for you!
It is a good idea to research your processor online before Overclocking because it is likely that others will have Overclocked it and posted their results so you can use their results to get an estimate of what you are likely to reach depending on your cooling techniques. There are special Overclocking competitions held around the world where teams attempt to get the highest speeds and scores they can. They go to the extent of using liquid nitrogen to cool their processors so it really can get extreme! Speeds of up to and above 5Ghz are achieved in these kinds of competitions.
This is only a basic guide to Overclocking though, to really get the highest speeds etc you’ll need to properly understand the fundamentals of how a computer system works together. Basic Overclocking is good for anyone interested in computers that already know the basics of computers. Just remember to take things slow and if you are unsure about settings in your BIOS don’t change them since it could cause all kinds of problems. Research your processor and motherboard BIOS before carrying out anything. I wouldn’t recommend any beginners change any voltage settings since it likely won’t be needed for small Overclocks and is dangerous if you get it wrong! If you feel your PC is lacking power and want an extra little boost then definitely give it a go!




















