How to Upgrade Your Computer’s Processor


One of the simpler upgrades to perform on your computer is the CPU upgrade. Upgrading the CPU involves determining the effectiveness of the upgrade, selecting the right CPU for your system, uninstalling the existing CPU, and installing the new CPU. In this article, we will discuss the reasons for upgrading the CPU and then demonstrate how to do so.

First, is a CPU upgrade necessary? To answer this question, you have to consider the tasks that you regularly perform on your computer. If your computer is at most a few years old and all you do is surf the web, check email, and write papers, then you probably do not need a new CPU. On the other hand, if you play the latest games, edit photos, or encode video, then a CPU upgrade may be appropriate. If your computer is feeling sluggish and you are thinking about a CPU upgrade, first check to see if the CPU is responsible. To do that, check to see if the programs you run are CPU intensive.

Task Manager
Using the Task Manager to monitor your CPU usage (doesn’t look like I need a CPU upgrade).

A good way to check your CPU usage in Windows XP and 2000 is to utilize the Task Manager. To access the Task Manager, hit Ctrl-Alt-Del and click on “Task Manager,” and then select the Performance tab. Then, proceed with using your computer regularly, and check the “CPU Usage History” graph when you are done to see if your computing tasks are CPU intensive. You will know that they are if the majority of the graph is at or near 100%. If your computing tasks are CPU intensive, then a CPU upgrade will most likely improve the performance of your computer.

Is It Practical?

Having determined whether a CPU upgrade would be beneficial, you must now determine whether it is practical and possible to upgrade your CPU. Because the level of CPU technology advances so rapidly, a computer from just a couple of years ago may not have an available CPU upgrade path. Check with your computer dealer, the manual, or use diagnostic software to determine what type of CPU you have. A program that I like to use is CPU-Z. Once you have determined the type of CPU in your machine, you need to find out what options are available for your system. If, for example, your computer has (for its generation) a top-of-the-line CPU, then your options may be limited and any possible upgrade would bring very little benefit. Here are some terms you should be aware of when performing your research: front side bus (FSB), socket type, chipset support, core voltage, motherboard compatibility, special instructions (MMX, SSE, 3DNow!, etc.).

Athlon XP
An AMD Athlon XP Retail Processor

Once you have determined that upgrading your CPU is indeed viable and possible, it is time to acquire the new CPU. CPUs are sold as retail or OEM (original equipment manufacturer). Retail CPUs usually come with a longer warranty (years instead of months or days), a manufacturer-approved heatsink/fan (HSF) unit, and detailed installation instructions. OEM CPUs come with only the CPU itself. Naturally, retail CPUs cost more, but depending on the price difference, they may be the better value. One last thing to consider is the HSF unit. Make sure that the HSF unit you decide to use is capable of dissipating the heat the new CPU generates. Of course, if you are buying a retail CPU, you do not need to consider this point.

Performing the Upgrade

Finally, we can proceed with the actual upgrade. First, you will have to remove your existing CPU:

Before Upgrade
The CPU area before the upgrade
  • Unplug your computer, open the case, and ground yourself to prevent static damage.
  • Unplug the CPU fan from its power source (either the motherboard or a Molex connector).
  • Remove the HSF unit. You may need to use a flathead screwdriver to push down the clip holding the HSF to the socket. Be very careful with this step.
Lever Up
The lever in the “up” position
  • Remove the old CPU by pulling out and up the plastic or metal lever, and then lifting out the CPU by its sides.

Reverse the above steps to install the new CPU:

  • Insert the new CPU, being sure to match the pins to the holes. The CPU will only fit in one direction and will not require any force to insert. If you need to force it in, the CPU is incorrectly oriented. Once the CPU is in the socket, lower and lock the lever.
  • If your HSF unit does not have some already, apply a thin layer of thermal compound to the CPU core.
Side View
Notice how the bottom of the heatsink is parallel to the CPU core and touching it
  • Install the HSF unit, being sure to orient the HSF unit such that the CPU core is completely flush against the bottom of the heatsink. Again, you may need a flathead screwdriver. You must also be very careful with this step so as not to damage the CPU and/or the motherboard. Remember, if you power up your system without the HSF unit properly attached, you will cause permanent damage to the CPU!
Fan Unplugged
The CPU fan header without a fan plugged in…
Fan Plugged In
…and the same with a fan plugged in
  • Plug the CPU fan into the proper power source.
  • Do not close the case (yet).

Before closing the case and finalizing the installation, plug in and power up your computer to verify that the new CPU is working properly. Confirm that the CPU fan is spinning. Carefully touch the heatsink to make sure it is warm. Check the CPU temperature in the BIOS to make sure the temperature is not rising rapidly. Verify that you can boot into your operating system. If all of the above check out, congratulations! You have successfully upgraded your CPU. Power down the computer, close the case, and enjoy your new CPU. If, on the other hand, the results are not what you expected, consult the troubleshooting section below.

In this article, I have described some reasons for upgrading a CPU, whether it is practical to upgrade a CPU, and how to upgrade a CPU. In many cases, a CPU upgrade is very beneficial, but in many other cases, a CPU upgrade is just a waste of money. I hope that after reading this article, you will be armed with the information necessary for making the right choice.


If nothing happens when you power up the computer, try the following steps:

  • Verify that the CPU is inserted correctly into its socket.
  • Verify that the CPU fan is plugged in. If your CPU fan is plugged into a Molex connector, plug a spare fan into the CPU fan header on the motherboard and try to power up. If you can, then your motherboard was preventing power up because it detected no CPU fan. You can turn this feature off in the BIOS.
  • Verify that the HSF unit is installed correctly.
  • Verify that you did not accidentally knock loose another component (such as a memory module) when installing the new CPU.
  • Clear the CMOS: unplug the computer, and then check your motherboard manual for a jumper setting to clear the CMOS. If your motherboard does not have a clear CMOS jumper, remove the flat, silver battery from its socket for at least ten minutes, then re-insert it.

If none of the above work, try the CPU in a different motherboard (if possible). Otherwise, you may have a defective CPU and should have it replaced.

If your CPU boots but the CPU speed is not as advertised, try the following:

  • Verify that you have set the FSB speed properly in the BIOS and/or with a jumper on the motherboard. Check your motherboard manual for details on how to do so.
  • Verify that the CPU multiplier is set correctly in the BIOS and/or with a jumper on the motherboard. On newer motherboards, this should not be an issue.