Core 2 Duo Basic Overclocking guide for beginners.
This guide is intended as a quick and easy way to get overclocking your C2D CPU - The guide is also
available in French, thanks to Zenoth for the translation
(We can not offer any French language technical support at this time ) and there is also a P5K Add-on and a new DFI Add-On.
I will assume that your pc is stable at stock speeds, overnight
Prime 95 /
Prime95x64 before you start. I will also assume that you have some kind of aftermarket CPU cooler and decent case air flow and ventilation. The stock Intel coolers are fine for running at stock speeds, but they aren’t too great for overclocking.
I’m going to keep this guide as simple as possible, as it is aimed at people who aren’t necessarily "enthusiasts", but would like to benefit from the extra bump in speed that can be had by overclocking their Core 2 Duo CPU.
You will need a few pieces of free software; The last two in the list are optional and we will be using them for testing the memory later on.
Also, see
Death's Overclocker's Toolkit for all the latest handy software.
Overclocking.
Every piece of hardware is unique. No two CPUs, no two sets of
RAM, no two motherboards will give exactly the same results, so keep this in mind when you start overclocking.
You might have a friend that has all the same gear as you, and yet he can overclock his quite a bit higher. Don't worry! - A lot of this is pot luck, some of it is knowing your hardware, and a small part of it is patience. The rest of it, you'll pick up as you get a feel for how things work.
A quick note on Power Supplies before we start.
One of the most important parts of the computer is the power supply (
PSU). This is often overlooked when budgeting for a new PC, and people end up with the generic
PSU that comes with a cheap case, or an unbranded
PSU, and often think that this is ok.
In some cases, these work fine, and can give years of service, the trouble is, when they decide to break down, they tend to take other components with them.
Imagine spending a grand or more on a new PC, only for the cheapo
PSU to blow, taking your £300 graphics card, your CPU and your
ram with it, all because you scrimped on the
PSU!
The bottom line is - Don’t scrimp on the PSU.
Get yourself a decent branded
PSU, from a trusted manufacturer. If you are unsure of your individual power requirements or need help with different brands of
PSU, please ask on our forums.
A note on RAM.
To give you a rough idea of what
Ram to buy, PC2-6400
ram, will give you a theoretical CPU overclock of 3.6ghz on an E6600/E4300, 3.2ghz on an E6400 and 2.8ghz on an E6300, these figures represent the maximum CPU overclock without even overclocking the
ram. More on the ins and outs of that later on.
For the purposes of overclocking, grab yourself something like PC2-6400
ram as a minimum. Try and avoid cheap, unbranded or generic
RAM. I know from experience, it can be more trouble than it's worth.
RAM is quite cheap at the time of writing this guide (13/03/07), so no need to scrimp on the
RAM either.
Update - 25-02-08: DDR2 is so cheap at the moment, you can get 2x1GiB of excellent overclocking
RAM for well under £50 (and 2x2GiB for around the same price), so I would recommend something along the lines of PC2-8500. Please ask on the forums for more advice on memory.
What CPU should I get?
Obviously, this will depend on your budget. The great thing about C2D CPUs is that the majority of them will overclock well. By this, I mean that with very little skill and effort, you could take your 1.8ghz £99 CPU to 3.0ghz and beyond. (If you are reading this bit and thinking "3ghz? Is that all?", this guide isn’t for you, try XS for something not aimed at first time over clockers
).
Important Terminology.
Lets have a quick look at your CPU and get used to some of the terms that will be used a lot in this guide.
Click on each item for a more detailed description.
Above are the stock values of the most popular C2D CPUs. (I have left out the Xtreme models for now, as most people reading this guide wont have one of those.)
As you can see, the
FSB x the Multi = the speed in Mhz (Are you with me so far?)
When you see C2D CPUs advertised, you will probably have seen that they are shown to have 1066
FSB, this is just referring to the 266
FSB mentioned above, but "Quad Pumped".
Here is a technical explanation for those who care.
We will be using the normal (lower =
266/1066) values for the purposes of this guide as shown in the table above.
The CPUs in the table above, have multipliers that are "Upward locked". This means that you can't change the multiplier upwards in the
BIOS, however, you can change it downwards, but for now, we don't need to bother with that.
As the multiplier is locked, we need to increase the
FSB. Increasing the
FSB results in higher Mhz, so for example:
As you can see, when you raise the
FSB, you get a higher speed in Mhz, and in theory, a much faster CPU. (Still with me?)
The above examples can be applied to any C2D CPU, but CPUs that have a lower multiplier, will end up with a higher
FSB to reach the same Mhz, see the table below.
**So, looking at the above table, you can see that the
FSB has to be 515 on an E6300 to reach around the same Mhz as the E6600 at 400
FSB. This can put a real strain on the motherboard, and often requires a lot of extra voltage to the Northbridge and CPU.
For now, we wont be worrying about really high FSBs (over 400 say), as when the
FSB becomes very high, there are a lot of other variables to consider, and after all, this is meant to be a guide for beginners
.
Hopefully, now, you should now have an idea of what we are trying to achieve, and we can get down to business!
I am going to be using the Asus P5B Deluxe WiFi AP for reference (I've now added some Abit Quad GT pics as well, thanks to Daza
), an E6600 and I will provide as many
BIOS screen shots as possible, so you can easily see what I have done. The
BIOS screenshots may vary slightly from yours, but everything should be worded similarly (ish).
Ensure that you have the latest
BIOS for your motherboard. Also, before you start overclocking, try and familiarise yourself with the
BIOS, and what some of the basic functions do. If you built the PC yourself, you will have been into the
BIOS to set the clock and date etc, so, from now on, I am going to assume that you know how to set things, save and exit, clear the
CMOS and so on.
Ok, lets fire up the PC and get into the
bios.
The first thing that I usually do, is enter the
RAM timings and set the
RAM voltage (VDIMM).
The reason for this is that some
RAM/motherboard combos are known to be picky about start up voltage for the
RAM, meaning that most motherboards default to 1.8v which is the
JEDEC standard for DDR2, and a lot of
RAM, especially performance
RAM, requires more than this, some as high as 2.5v, and as a result wont start properly after the first boot.
Even if your motherboard and
RAM aren't affected with the above problem, just do it anyway, get into the habit.
Abit Quad GT users Click Here!
In the screenshot, you can clearly see all the timings for the
RAM. It is important that you enter these to get the best performance from your
RAM. If you don't enter these timings manually, the motherboard will read the
SPD table of the
RAM and run it at the standard, relaxed, safe, timings. This is ok, but not optimal.
While we are in the
BIOS, disable anything that you aren't using, this part is optional, but I always do it. Things like onboard sound (if you have a soundcard), Firewire (if you don’t need it), IDE controller (if you don’t have any IDE devices), you get the idea anyway!
Save all that, boot to windows, check everything is working ok and then back to the
BIOS.
This time we are going to set the
RAM to 1:1 (meaning that the
RAM will be running synchronous to the
FSB) This bit might sound a little bit confusing at first, but it needn't be.
DDR is
Double
Data
Rate, so when you look at the
RAM Divider settings in the
Bios (see the screenshot below), you will see that if the
FSB is set to 266, the
RAM will be set to 533, this is what is known as 1:1.
DDR=
Double
Data
Rate = Double the
FSB value.
Abit Quad GT users Click Here!
Here is a quick explanatory table.
You get the idea?, whatever the
FSB, just double it to give you the
RAM 1:1 value. 400
FSB would equal 800Mhz
Ram and so on.
So, we have set the
RAM to 533 and the
FSB is already at 266. Before we go any further, please change these settings so they look something like the next pic.
Abit Quad GT users Click Here!
Once thats done, lets up the
FSB a bit. Change it to 300,
Abit Quad GT users Click Here!
did you notice that the
RAM has changed to 600? This is correct. For now, set your CPU voltage (Vcore) to Auto
**. Leave all the other voltages on auto for now as well. Save and exit.
**A quick note on voltages.
A lot of people ask what is a safe voltage for their CPU, how high they should push it, and what the max temps should be.
The answer is...there are no safe voltages above the stock voltage. Look on the side of a C2D box and you will see something like "1.35v MAX", anything over this and you not only invalidate your warranty, but you also run the risk of long term damage to the CPU.
The thing that Will damage your CPU is setting the PLL voltage too high. This has different names on different boards, and we don't need to go into it here as we aren't adjusting it, but, if you are unsure, please ask for help.
Your temps are going to depend largely on what voltage you feed the CPU, but there are many other factors to consider, so it really is impossible for me to give a figure as to what your temps should be.
Some of the deciding factors include;
- Vcore (CPU Voltage)
- Speed of the CPU
- Cooler used
- Thermal Paste used
- Measuring Software used
- Accuracy of the CPU's on board sensor
- Flatness of IHS
- Flatness of Heatsink
- Type of fans used
- Number of fans used
- Speed of fans used
- Case Airflow
- Case temp
- Heat from other components
- Room Temps
- Water temp
- Pump Speed/flow
- Type of Radiator
The list goes on and on.
So, hopefully you can see that comparing temps, doesn't really mean anything.
To account for lesser coolers, I have mentioned 65c as a *rough* max level to max temps in this guide, but if you have awesome cooling, a hurricane blowing through the case, a chilled room and a perfect surface between the CPU IHS and heatsink, then obviously, your temps are going to be much less than the person that is running the stock cooler, in a cluttered case, in a hot room with a concave IHS on the CPU.
By the same token, if you own a Q6600 B3, you will probably find that your temps will exceed 65c easily, and in that case, just go with what YOU feel ok with. I tried to keep things under 75c.
Back to it....
All being well, your PC should boot straight to Windows now. Once you are fully booted into Windows, open CPU-Z (it can take a few seconds to open) and you should see something like this...
You can now marvel at your work for a second, have a look at the
RAM section of CPU-Z, it should look something like this..
After you have finished marvelling, you can close CPU-Z, it was just to show you the changes that you have made
We want to have Coretemp and possibly another temp monitoring program (or software of your choice from
Death's Overclocker's Toolkit). The reason for two different temp monitoring programs is that I have found that on some CPUs, the temp sensor shows wildly different temps, and we want to be keeping an eye on the temps.
Update - 25-02-08: As things have moved on since I first wrote the guide, and now, you can generally get away with just CoreTemp - Vista x64 users of CoreTemp have a look
here for some tips on getting up and running.
Open your stress testing program and make sure that it is set to the "blend test" and set it going. Your temps will now rise as the CPUs cores are under heavy load, this is normal and is exactly what we want
.
Leave your stress testing program running. Keep an eye on the temps, I would say for a relatively modest overclock like this, we don’t want to be hitting 65c, and I would hope that the temps would be much less than this. If you find that the temps are higher than this, then you have a problem and you need to read the
troubleshooting part of this guide.
If you are happy with the temps, leave the stress testing program running over night if possible, or for at least 12 hours if you are a genuine nerd.
.
Some might argue that there is no need to do this, but I disagree and this is how I do it. 12 hours it is. If you get errors in your stress testing program, or it says "STOPPED" or the PC locks up, or reboots, you also have a problem and need to check out the
troubleshooting part of the guide before you continue.
For most people, the stress test should run over night, or for 12 hours with no problems. Once this is done, you can continue with your overclock as your PC is now stable.
Restart and get back into the
BIOS. (Keep in mind that as you up the
FSB, the motherboard will automatically up the CPU voltage (Vcore) if it is set to AUTO**, so it is important that you keep an eye on the temps, once you are running the stress test.)
Now lets try upping the
FSB to 320. Exactly the same as last time, same testing, keep an eye on the temps again, and that is it………until you get to the point where it fails the stress test instantly (or after a few minutes), or wont boot to windows.
If that happens, simply go back into the
BIOS and lower the
FSB slightly, save and exit, then try again, keep doing that until you can run the test.
You may find that you get to a point where it is stable, but the temps are a bit too high for 24/7 use, and in that case, it is best to keep lowering the
FSB until you find a point where you are happy with the temps and performance.
Alternatively, if you have a really good CPU cooler, you can try feeding the CPU a touch (one notch) of voltage (Vcore) and then retesting, but keep a close eye on the temps if you are doing this.
There's lots more to it than just this, but this should hopefully get some of you up and running pretty quickly.
If there's something that you don't understand, please click here to register and ask on the forums
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DFI BIOS Guide - Click Here!
C2D Overclocking Guide For Beginners - DFI Add-On
C2D Overclocking Guide For Beginners.
