Right here we go!
Here are a few key words you need to know:
Base Clock: affects your CPU frequency, RAM frequency, and other things. We won't be tweaking it in this guide, but we'll be using it to calculate our final clock speed.
Multiplier: Coupled with the base clock, your CPU multiplier decides your final CPU frequency. It works like this: if your base clock is, say, 100 MHz and your multiplier is 35, your CPU frequency will be 100 MHz x 35 = 3.5 GHz.
CPU Vcore: is the main voltage value we'll be tweaking. As you increase your clock speed, you will likely have to raise your Vcore to supply your processor with enough power.
Front Side Bus (FSB): is what determines the CPU frequency. For example, say if you have a CPU frequency of 1.6Ghz and a FSB speed of 533Mhz, that means that your CPU multiplier is 1.6/533=3. This means that for every time you raise your Front Side Bus' speed, you'll raise the CPU frequency by three times as much.
Before we start, overclocking is a pretty safe process if carried out correctly. If not, you may permanently damage your system components. I strongly recommend that you set yourself a target clock speed to aim for and most importantly, that you have Patience. For example, you should only increase the multiplier by 1 each time, stress test the system and if all is ok, increase again and so on. If you are greedy and increase it massively, you could fry the system. The moral: You can never be too careful when overclocking.
There are two methods of overclocking, through the BIOS and software overclocking.
What You'll Need:
A Windows machine: This guide is for Windows, though if you have a Mackintosh or a Linux machine with a Windows partition, that should do fine—we're just going to do our stability testing in Windows.
An unlocked, "K" series Intel/AMD processor: This guide was written with Intel's/AMD's more recent processors in mind, particularly the "K" series processors designed for overclocking. They'll have a K in their model name (e.g. i7-4770K/Athlon II X4 750K). If you have a first-gen Core i series processor, overclocking is a bit more complicated, but this guide should get you started. You can overclock other processors too (like Intel's low-powered Atom), but for this guide we'll be focusing on these. AMD users can probably follow many of the steps, but you may have to look up some additional information on your processor's settings first.
An overclocking-friendly motherboard: Lots of motherboards should have overclocking settings built-in, but some motherboards have more settings than others, or are better suited for overclocking. If you're building a computer with the intent to overclock, you should read up on your motherboard's overclocking features before you buy.
CPU-Z: This is a handy little program that shows you the values of your clock speed, voltage, and so on once you've booted into Windows, so it's a handy way to see whether your settings are working correctly.
Prime95, LinX, and/or AIDA64: You'll need one or all of these programs to stress test your CPU and ensure that it's stable. They will push your chip to the max, so you can see if your computer crashes or gets too hot. There's a lot of debate over which is the better stress tester, but we won't get into that here—honestly, I believe in using some combination of the three, and will note how I use them in the guide.
Optional, A decent CPU cooler. For a minor overclock you can use the stock cooler which came with the processor but for a major overclock, you will need a good aftermarket cooler, though not necessary, it would give you more headroom.
Step One: Stress test your default settings.
Though this step isn't necessary, I decided to include it since you can never be too sure that even your default settings are completely stable.
1. Restart your computer.
2. Keep hitting either the 'delete' button or F2/F8/F10 (depending on your system's BIOS). This will Bring you into the BIOS menu.
3. Find the 'Load Optimized Defaults' text or something similar, click on it and then exit the setup.
Once you've done that reboot Windows and launch the AIDA64 Utility and click on 'System Stability Test' (the one that looks like a computer monitor with a green graph on it). Check all the boxes in the upper left-hand corner, and start the test. Let it run for a few hours on its own to ensure your system is stable as-is. When you're done, click Stop, and move onto step two.
Step Two: Overclocking (Increasing the Multiplier)
Now it's time to start overclocking. You can google around and see what kind of settings other people have gotten, but I still recommend starting at your base clock speed and gradually ramping up—it takes a little longer, but it's much easier to do and ensures you get the best stable overclock by the end of the process.
So, boot back into your BIOS and head to its overclocking settings (they may be called "Overclocking Settings," or they may be called the "CPU Tweaker" or something like that).
Find the setting called CPU Ratio, or something similar. Right now, it's probably set to "Auto." Highlight it and change it to one step above the default (either by pressing Enter or typing in a number, depending on your BIOS). If you aren't sure what your default is, it's usually listed at the top of that Overclocking Settings page. For example, my CPU comes stock with a multiplier of 34 for a 3.4 GHz clock speed, so I set mine to 35 for the first step.
Once you've done that, reboot your computer back into Windows and head to the next step.
Step 3: Stress Testing you CPU
Now after gently overcloking your CPU, it's time to stress test it to see if your current setup is stable.
1. Check CPUz to see if all the tweaks you have made have been applied.
2. Use Real Temp to monitor the temperatures as you stress test. (Keep a sharp eye on these if you raise the Voltages)
3. Use any of the three programmes mentioned to stress test. Just a quick note that LinX provides a quick test while the tests by Prime95 and AIDA64 are more extensive.
For example, run LinX for 20mins. Your test will end in one of three ways:
1.The test finishes successfully within safe temperatures. If this happens, return to step two and increase the multiplier by another notch.
2.The system gets an error or crashes (BSOD). If this happens, the voltages aren't set high enough. If so, proceed to step four.
3.Your temperatures reach unsafe levels. Set a limit to what you think is the maximum temperature you want to reach. Remember, high voltages and temperatures could shorten your CPU's lifespan.
Step 4: Increase your Voltage
If your stress test failed or BSOD'd on you, don't worry! It probably means your processor just isn't getting enough voltage to keep a stable clock speed. So if that happens, just raise the voltage.
Head back into your BIOS' overclocking settings, like we did in step two, and find your "CPU Core" or "Vcore" value. Raise it a little bit from its current value. I usually raise in increments of 0.05 (e.g. from 1.2000, my CPU's default value, to 1.2500).
When you've finished, save your changes and reboot your computer. Then, repeat step three. Remember, the higher you raise your voltages, the higher your temperatures will get, so keep a close eye on them!
Step Five: Rinse and Repeat!
Now, repeat this process (steps two through four, as governed in step three) until you reach your maximum safe temperature or your maximum safe voltage (again, Google your specific CPU for more information). When you reach this point, back your settings down to the last safe and stable value. I got my multiplier up to about 43 before my temperatures reached my limit, so 4.3 GHz was my final overclock.
Once you've done that, save your settings and reboot into Windows for some final stress testing.
Wow! after an hour, this guide is done! Hope it is as informative as I think. Any questions? Just ask!