How To Overclock A CPU

There are several methods of how to overclock a CPU.  You can overclock to get your system faster, without having to sacrifice stability.  I will share with you the methods that I like to use.  If you're new to overclocking, use the first method of buying a system that has a CPU with an unlocked multiplier.

The most common method of overclocking is to buy a CPU that has an unlocked multiplier.  This is the easiest way to learn, and generally you'll achieve better overclocks with an unlocked multiplier.  Since a CPU has a much higher speed than the motherboard, the CPU multiplies the clock to get it's speed.  For example, if the bus speed is 100 MHz, and the CPU multiplier is 36, the speed of the CPU would be 3600 Mhz or 3.6 GHz.  An unlocked multiplier simply lets you change this value.

I will show you the BIOS method of how to overclock a CPU.  Most motherboards will not come with software that will let you overclock right in Windows.  The only reason I don't use these programs currently is because I often find them to be flaky.  They are great for finding the approximate max of a CPU to save some time however.

Little Programs to make it Easier

To learn how to overclock a CPU, you'll need a couple of programs that will help you make this easier, since you will be pushing the computer system, you'll need to make sure you don't damage everything.  All programs below are free to use and can be found on mother Google.

TIP! If you're completely new learning how to overclock a CPU, you need to be aware that you can damage computer hardware by doing so.  If you're careful it's unlikely but the chance is there.

  1. RealTemp - since the faster and harder the CPU works, the more heat it produces, you need this to make sure that you don't damage any hardware.  It will track your CPU's current temperature.  To use, simply start the exe file and the program will begin to monitor your temperatures.
  2. Prime95 - this is a useful little program to work the CPU to it's maximum in order to make sure that your overclocked system will be stable.  Run this program, usually it starts minimized to system tray.  To get the best test, open it up, click on options, the select torture test.  To stop, click on test, then stop.

How To Overclock A CPU With An Unlocked Multiplier

  • Step 1 - Boot into the BIOS, find your CPU settings and increase your stock CPU multiplier by .5 save changes and reboot the computer.
  • Step 2 - Assuming Windows has loaded, start RealTemp and Prime 95 to work your CPU at it's maximum for atleast 10 minutes.  Make sure to monitor the temperature, if you get up to 60 degrees Celsius, stop Prime 95 immediately.  Reboot the computer and go to a slower setting.  (Temperature is up to you, research your exact CPU to find the limits.)
  • Step 3 - If you ran for 10 minutes and everything stayed cool and nothing crashed, great, let's go faster.  Start at Step 1 again.
  • Step 4 - Did your system stay under 60 degrees Celsius but crash?  If so add voltage by the smallest increment available to the vcore of the CPU.  This is also done by booting into the BIOS settings.  .15 volts over stock should be pretty safe, again, research your exact CPU and see what safe limits are.  Patience is what give you the killer overclocks you read about.

How to Overclock a CPU with no Unlocked Multiplier

  • Step 1 - Get a little program called CPU-z.  Find your current memory timings in the memory tab.  Then click on the SPD tab and write down the next lower settings.
  • Step 2 - Boot into the BIOS, change the speed of HT Link to one step lower than the default.
  • Step 3 - Change the RAM timings to those we got in Step 1.  Some of you now thinking, wait, we're actually decreasing the speed on HT Link and RAM.  You are absolutely correct.  But since they are all related to the multiplication of the FSB, we must slow the other elements down, since we are only looking at CPU overclocking.  Otherwise, we wouldn't just be CPU overclocking, we would also be overclocking the HT Link, and the RAM at the same time.  You can't ignore these steps and expect any kind of result.
  • Step 4 - Increase your stock FSB by 5 save changes and reboot the computer.
  • Step 5 - Assuming Windows has loaded, start RealTemp and Prime 95 to work your CPU at it's maximum for at least 10 minutes.  Make sure to monitor the temperature, if you get up to 60 degrees Celsius, stop Prime 95 immediately.  Reboot the computer and go to a slower setting.  (Temperature is up to you, research your exact CPU to find the limits.)
  • Step 6 - If you ran for 10 minutes and everything stayed cool and nothing crashed, great, let's go faster.  Start at Step 4 again.
  • Step 7 - Did your system stay under 60 degrees Celsius but crash?  If so add voltage by the smallest increment available to the vcore of the CPU.  This is also done by booting into the BIOS settings.  .15 volts over stock should be pretty safe, again, research your exact CPU and see what safe limits are.  Patience is what give you the killer overclocks you read about.
Once you think you're at the maximum, do a CPU stress test to make sure that the computer is stable, if it is, you're good to go, at least until you want to push it further.

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Updated October 14 2013

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