C2D Overclocking Guide for Beginners

[Clunk]

Part 2.

A Fully Updated and Supported Version Of This Guide Is Available At Clunk.org.uk

In Part 2, we will be looking at tweaking voltages and tightening memory timings, and generally optimising your PC, now it is overclocked.

At this point, as we are going a little bit more advanced, I will assume that you have read the other parts of the guide, and you have got to grips with how things work, and how to recover if you stuff it up (a bad overclock, see the troubleshooting guide).

Disclaimer.

Please read this bit, it is very important!

RAM is potentially the easiest thing to kill in a PC. Overvolting any component carries a high risk of damage and/or failure. I take no responsibility for any loss or damage to your components as a result of using this guide. All overclocking is done at your own risk.

A lot of RAM, just will not overclock much, no matter how much voltage you feed it, so if things aren't working out for you in this part of the guide, leave it right there, and seek help on the forums, rather than throwing more voltage at it.

Tightening up those timings.

Now you have a nice, stable, fairly large overclock, we can look at tightening the RAM timings.

At this stage, be prepared for some CMOS clearing, BSODs, and general odd behaviour from your PC to start with, but it will be worth it

If your RAM is already running tight timings, such as 3-4-3-8, then there is no great need for you to follow this part, you can skip to the voltage tweaking part further down.

If you have some RAM that uses Micron D9xxx chips (Check here to see if yours are), you will probably have more success at this point than people that aren't. The Micron D9 chips can often do really insane tight timings at quite high speeds, but often require a good slug of voltage to get there. Some sticks are rated for up to 2.45v, but for this kind of RAM, you need active cooling. Its pretty simple, the higher the voltage, the hotter the sticks will get, and the hotter they get, the more chance you have of getting errors, or even killing the RAM outright, so you need active cooling.

By active cooling, I just mean a fan, directly blowing on the RAM to dissipate the heat that is generated.

I have found that an 80mm or 92mm fan, blowing at a moderate speed from a couple of inches away, is enough to keep most D9 RAM happy (alive ), a 120mm fan has too big of a dead spot, in case you wondered.

There are also dedicated RAM coolers that you can buy, from the likes of OCZ and Corsair, which also work well.

My general rule of thumb is that if the RAM is 2.0v or over, blow a fan on it. Better safe than sorry.

So, what I'm getting at, is keep the RAM cool.

OK, back to the timings.

Some applications benefit greatly from tightened timings, other don't, all you need to do, is find a memory hungry program that you use a lot, and try tightening your timings, if you can see a benefit, then great, if not, change them back and forget about them

Install Sisoft Sandra 2007. There is a very useful memory bandwidth benchmark in there. Run it now and make a note of your current memory bandwidth.

So, my RAM is rated for 5-5-5-12 @ 1066Mhz (PC2-8500)

This will often mean that if I were to run it at less than the rated 1066Mhz, say at 800Mhz, I could then tighten the timings, without having to up the voltage (not always, but more often than not).

So, if I go into the BIOS, and look at my existing settings, I have an FSB of 380, and the RAM running at 760Mhz with timings of 5-5-5-12.

Now, I know that the RAM will go higher at those timings, so in theory, can go tighter, at a lower MHz, so I will change the 5-5-5-12 timings to 4-4-4-12 and see what happens.



Save and exit the BIOS.

Hold breath.......

If it hangs or doesn't post, don't worry, it is just your Memory's way of telling you that it doesn't like going that fast, and that it needs more voltage (see disclaimer), or looser timings.

If it boots to Windows, run the Sandra memory bandwidth benchmark and record your score again.



Run Orthos/Prime/SP2004 again, if you get errors, you know its the RAM, so you will need to up the voltage by one notch.

Save and exit, boot to windows, and test again.
Is it stable this time?

If not, repeat the above steps and add another notch of voltage to the RAM, but at this stage, if that doesn't work, its probably safe to say that your RAM doesn't overclock well, and to leave it at stock timings/voltages, rather than damage it.

If it IS stable, then that is good news, run the Sandra 2007 memory bandwidth benchmark and record your scores.

Now, if you are feeling adventurous, you can try for even tighter timings, maybe something like 4-4-4-4, or 3-4-4-8.

Run Sandra again.


So, not much of an improvement in bandwidth, but the changes should be noticable in *some* real world applications, that part is up to you to test

Keep a note of all your scores, and if you have a bit of software that you use a lot, try out your new settings on that as well.

At this point, it is just a case of finding out what your RAM is capable of, and if the performance is worth the trade off in heat and voltage.

Once you have found a set of timings that you like, and are stable, save these BIOS settings to a USB stick for use later, using the Asus O.C.Profile,



Next, we will see how high your RAM can go using a divider.

If you haven't used a divider before on a C2D board, there isn't much to it really, on Intel chipsets, they only go upwards, in other words, they will only let you run your RAM faster than the CPU.

While we have a play with these, we will put the FSB back to 266 for now, so I can explain things a bit easier.

At 266 FSB, we have a set of dividers available to us.



There are dividers to allow you to run your RAM at;

667Mhz
800Mhz
889Mhz
1067Mhz

So, lets say that your RAM is rated at 800Mhz, choose the 800Mhz divider (it can be any within reason), and make sure that your RAM timings and voltages are set to their normal values.

Try upping the FSB a bit to 300, this will now set the RAM to 720Mhz, and we know that your RAM can do at least 800Mhz, so lets go up a bit more, try 333 again (Deja Vu?), this will give you bang on 800Mhz on the RAM, but only 3GHZ on the CPU, so we need to raise the FSB a bit more to say, 350, that gives us 840Mhz on the RAM and 3150Mhz on the CPU. Its not a huge overclock, but it is on the way.



Save and exit, boot to Windows, exactly the same as before, if it boots, all is good, if it doesn't, you have gone too far, so either back off the FSB, or add a notch of voltage to the RAM (see disclaimer).

OK, so we are safely into Windows, run Sandra 2007 memory bandwidth benchmark again and make a note of your results again.

Run Orthos/Prime/SP2004 again, I like to use the blend test for all of these tests, so that everything gets a good stressing.

Remember, this bit, is just an exercise to get you acquainted with dividers.

Have a mess around with some of your regular programs again, see if you can notice any difference.

Of course, it doesn't end there. For those of you with faster RAM, you can go back to the BIOS and choose a higher divider, and see how high you can go.

Next up, we are going to try and find a good balance between your high CPU overclock, A high RAM divider and the tightest timings possible.

At this point, I will assume that you have tested how high your RAM will go, and have made a note of the speed

Same for the timings

Same for the CPU overclock (although, you should have saved the settings in O.C.Profile)

Load up your Best stable CPU overclock from O.C. Profile.

Now choose a divider that is as close to your RAM's max as possible, but without going over.

Keep the RAM timings standard for now.

Set the RAM voltage to whatever you had it at when you found it's max speed.

To aid stability, you can also change the Northbridge setting from AUTO to something like 1.55v. (This isn't always 100% necessary, and you can always change it back later).

Save and exit, and boot to Windows.....

If it doesn't boot, or if it hangs, or you get a BSOD while loading Windows, there are a few things you can try;

A different divider, preferably lower, but sometimes a higher one will work.

A notch more voltage to the Northbridge.

A bit less FSB, try dropping it by 10 at a time.

Try again.

Once it's stable, you can try the tighter timings, but you may need to drop the FSB by say, 30-50 and work your way back up.

All of this is just a balancing act, and, after a while you will definitely get a feel for what will and what wont work.

Don't worry if something doesn't work, just keep experimenting, and you will get there eventually.

Part 3

Voltage Tweaking

This section is for those who want to keep their overclock, but want to lower their heat output (Not by much, but it's better than nothing )

This is pretty much, just common sense, and a process of elimination.

So, your PC is rock solid stable, but there's an awful lot of hot air coming from the exhaust fan, what can you do?

Anything voltage related that is set to AUTO, simply set it to its lowest value, manually. Do this one item at a time, test for stability, and then do another. That way, if you adjust a few things and it turns out to be unstable, you don't have to guess at what it was that you changed.

Vcore is probably the biggest source of heat. Unfortunately, when you overclock, you will generate extra heat, even if you don't add extra voltage, but you can try and reduce the amount of Vcore that you use.

Simply drop the Vcore to whatever you think, and then test with Orthos/Prime/SP2004, if it fails, it needs more Vcore, simple as that. Try upping the Vcore in single notches until stable again.

You can always back off the FSB, but that kind of defeats the object of all the hard work we have just done.

Again, its a trade off between temps and performance, the choice is yours







As always, if you think I have missed anything, or if you want to see something included in the guide, please let me know.

P.S. theres more pics to come, and I'll be tidying it up and adding stuff in the coming days



Administrator message: Whilst the images for this thread have been hosted by HEXUS on this occasion we must advised that by following or acting on any of the information contained in this thread is entirely at your own risk. HEXUS Limited is in no way endorsing or recommending the content within this thread nor is it responsible for any loss or damaged caused, whatsoever.

[Clunk]

Core 2 Duo Basic Overclocking guide for beginners.


A Fully Updated and Supported Version Of This Guide Is Available At Clunk.org.uk

This guide is intended as a quick and easy way to get overclocking your C2D CPU.

I will assume that your pc is stable at stock speeds, overnight with Orthos 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;

Orthos
CPU-Z

TAT (Intel Thermal Analysis Tool)

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, 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 will 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!

Don’t scrimp on the PSU.

Get yourself a decent branded PSU, from manufacturers like Corsair, Seasonic, Enermax, Silverstone or Tagan. If you are unsure of your individual power requirements, please ask on the forums. You may find that you need much less than you think!


A quick 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, generic RAM, from experience, it is more trouble than it is worth. RAM is quite cheap at the time of writing this guide (13/03/07), so no need to scrimp on the RAM either really.

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.

Multiplier - A technical explanation here
FSB - A technical explanation here
Northbridge - A technical explanation here
Southbridge - A technical explanation here
BIOS - A technical explanation here

*****MORE TO BE ADDED SOON***********



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 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 to reach around the same Mhz as the E6600 at 400 FSB. This puts 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 cmos etc.

Ok, lets fire up the PC and get into the bios.

The first thing that I do usually, 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 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 arent affected, 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 table 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. See the pic below.

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.

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 TAT (Intel Thermal Analysis Tool) open (or one of those two plus the temp monitoring software of your choice). 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 a close eye on the temps.

Open Orthos and make sure that it is set to the “blend test” and set it going. Your temps will now rise as both of the CPU’s cores are under heavy load, this is normal and is exactly what we want . Leave Orthos 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 Orthos running over night, or for at least 12 hours. 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 orthos, 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, Orthos 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 Orthos.)

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 Orthos 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 get Orthos running stable.

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.


I think that is about it for now

There's lots more to it than just this, but this should hopefully get some of you up and running pretty quickly.

Hopefully we can make this a good information thread, and if you find the information useful, please rate the thread (Top Right), and submit it to DIGG by clicking on the DIGG link in the blue bar at the top of this guide.

Thanks to Daza for the Quad GT screen shots

Administrator message: Whilst the images for this thread have been hosted by HEXUS on this occasion we must advised that by following or acting on any of the information contained in this thread is entirely at your own risk. HEXUS Limited is in no way endorsing or recommending the content within this thread nor is it responsible for any loss or damaged caused, whatsoever.

[Colossous]

Nice 1 clunk !!

[Clunk]

Troubleshooting


A Fully Updated and Supported Version Of This Guide Is Available At Clunk.org.uk

From time to time, you may get to a point where the PC wont post after you have done a “bad overclock”, and it appears to be either dead, or you just get a black screen . Don’t panic yet! There are a few things you can try.

1. Unplug the PSU at the back. Often, just doing this for a few seconds is enough to let the motherboard reset itself, especially on a board like the P5B, which recovers well from a bad overclock. If that doesn’t work, on to step 2.

2. With the PSU unplugged, locate the CMOS clear jumper (see your manual for this) and move it into the “clear” position and leave it for a few minutes and remove the motherboard battery. While it is clearing, press the on/off switch on the case, this will help to discharge any electricity left in the capacitors on the motherboard. If this doesn’t work, on to step 3.

3. Repeat step 2, this time leave the cmos jumper in the “clear” position for a few hours, overnight if possible and also remove the RAM and make sure the battery is removed. If that doesn’t work, see step 4.

4. Remove the cpu and power on the board, as you would if there was a cpu in there, leave it running for about 30-60 seconds. Reset the cmos again, as mentioned in step 2. Hopefully you should be ok now.

5. If your PC is struggling at moderately low overclocks, make sure that you definately have the RAM set at 1:1. Since writing this guide, a few people have insisted on setting their ram to 800mhz (or whatever it is rated at) to start off with. Obviously this isnt going to work, as, when you start to up the FSB, the RAM speed will also increase and immediately, you will be running the RAM faster than it should go, resulting in an unstable system. If in doubt, set the CPU to 266 and the RAM to 533 and take it from there.

6. If you are having trouble getting stable at the FSB speeds mentioned in the guide, simply try some other speeds. Lets say that your board doesnt like 300FSB, well dont panic, try 310, and keep going until you find somewhere stable. This is normal and all part of finding out how your hardware works. Just keep an eye on the temps

7. If you are experiencing a jerky desktop, slow graphics performance, low framerates etc or any other kind of graphical corruption (this is mainly for Asus boards), load up CPU-Z and in the section that tells you about your motherboard, look at the bottom where it says something like PCI-E Link Width, it may have changed itself to 1x instead of 16x (this happened to me yesterday), so to fix it, go into the bios and cheange the PCI-E frequency from AUTO to 110 (you can try any value up to 110), save and exit, boot into windows and check with CPU-Z that the PCI-E Link Width is now set to 16x. If it is still at 1x, repeat what you just did, but up the PCI-E frequency another notch, check with CPU-Z and if it is back to 16x, go back to the bios and change it back to auto, and hopefully, it should be fine

8. If you are still struggling to get stable, another thing you can try is to swap the RAM into different slots. For example, if your motherboard (P5B) has black and yellow slots, and you have the RAM in the black slots, try the yellow ones. I find that the yellow slots work best for me on the P5B, and the black slots on the P5K, but as they say, Your Mileage May Vary

9. Your Multi is showing as 6x in CPU-Z, when it should be higher (8x, 9x, 10x etc), and your CPU speed is showing as much lower than it should be! - Go into the BIOS and under the advanced CPU settings, disable EIST/SPEEDSTEP. You should have already done this if you have followed the guide

10. On the P5K -
If you have a separate PCI RAID card, and are experiencing problems with drive detection, try disabling legacy USB.

11. Your PC2-8500 RAM (DDR2-1066) is showing as PC2-6400 (DDR2-800). This is because there is no JEDEC (Joint Electron Device Engineering Council) spec for PC2-8500, so the manufacturers use the highest existing spec for DDR2, which is PC2-6400. All this means is that you will have to manually set a divider if you want to run your RAM at PC2-8500 / DDR2-1066 (see the guide for more info on dividers).

12. CoreTemp fails to load when using Vista x64 - Reboot your PC and when it starts to reboot, press F8, and disable "Driver Signing Enforcement". When you get to windows, CoreTemp should now load up without any problems. This may work for other programs as well.

[Clunk]

reserved

[sswats]

Cool/

exactly what i needed

[Defenestration]

Thanks Clunk! Looks good on first glance.

This should be made a sticky!

[Agent]

Nice one mate

This will defo make it into the guides thread that will be coming up - with your permission of course

[Clunk]

Yep no worries

[owen1978]

Nice breakdown for beginners, overclocking should be encouraged. One of the most important thoings to overclocking is patience, dont expect to find the optimum clock within a few hours, normally it takes me a couple of weeks thats inc testing.

[excalibur2]

Thanks Clunk but I'm getting two dirty great black squares after:-

Even if your motherboard and RAM arent affected, just do it anyway, get into the habit .

and

So, we have set the RAM to 533 and the FSB is already at 266. Lets up the FSB a bit. Change it to 300,

Tried reload image in Opera and with firefox same problem.

[DecomposingStar]

[MadduckUK]

Thanks Clunk but I'm getting two dirty great black squares after:-

Even if your motherboard and RAM arent affected, just do it anyway, get into the habit .

and

So, we have set the RAM to 533 and the FSB is already at 266. Lets up the FSB a bit. Change it to 300,

Tried reload image in Opera and with firefox same problem.

is it because the pics are pretty dark and your brightness is way down? cause the pics are pretty dark

[mallett]

i thought that was class but i was wondering about overclocking the memory. i only have PC 5300 or 5400 (im not too sure which as iv seen it classed as both) 667 rated stuff (as in my system) so if i raise the fsb over 333 then will i have to slacken the timings or will the mobo raise the volts if i have them auto?

[tigerboyce]

So, we have set the RAM to 533 and the FSB is already at 266. Lets up the FSB a bit. Change it to 300

so entering the cpu fsb too 300 will give the 2.7ghz speed am i right?

[[GSV]Trig]

Nice one, havent oc'd one of my rigs for a while now as pretty much any new chip is fast enuf for the majority of things most people do.
Cyber beer for the guide tho