N00B intro to overclocking...

LONG AND BEHOLD.....my guide to overclocking...a little past the dead line...but not matter...enjoy...

Part 1

What is Overclocking?

In terms of a definition, overclocking is quite simple: it refers to changing the settings of a computer system so that the hardware runs at a faster speed than the manufacturer rated it for. Every piece of hardware in a computer system is tested and is supposed to be rated to run at a particular clock speed. When you overclock, you change the settings of the hardware so that it runs faster than what the manufacturer originally intended. Overclocking is also sometimes called pushing or speed margining.

There are many different ways that a system can be overclocked, depending on what part of the system you are looking to "push". The most common component is the system processor, but there are in fact several different ways to overclock a system.

Why Is Overclocking Even Possible?

To someone who doesn't understand a great deal (yet) about how PCs work, it may seem strange that you can run parts of the system faster than they are intended to run. Isn't a Pentium with MMX 166 always going to run at 166 MHz? The answer is "no". There are many parts of the PC that have the capability of running at different speeds. This is built into the hardware primarily for flexibility, to allow many different pieces of hardware to work together, and to make motherboard design simpler and cheaper.

The actual speed of your system bus and processor are controlled not by the processor itself, or by the chipset (which manages the system bus) but by jumpers on the motherboard. When you change these jumpers, you change the speed of the system bus or the processor. This allows many different speeds of processors to work on the same motherboard, and also allows chip makers to not have to have different internal designs for some of their chips. Some newer "jumperless" motherboards substitute special BIOS settings for these jumpers, but the concept is identical.

As discussed here, processor manufacturers always try to make their product as fast as possible, because faster hardware sells for more money. However, some chips turn out to be able to run at higher speeds than others. Each chip is tested to see how fast it will run, and the ones that will run faster are given faster labeling. This is called speed rating. So in a given family, some chips coming from the same wafer may become AMD K6-200s, and others AMD K6-166s.

The reason that overclocking works is that reputable companies are conservative in their speed rating. If Intel sends a chip out labeled as a Pentium with MMX 233, it wants to be darn sure that the chip will run at that speed. If there is any doubt of the chip's capabilities, it will be sold instead as a Pentium with MMX 200. Overclockers attempt to exploit this conservatism, sometimes with success and sometimes without. Occasionally a chip labeled at a lower speed will run at a higher speed, and sometimes it won't.

There is also evidence that in many cases, the processor manufacturer will at times intentionally underrate chips in order to meet market demand and create differentiation between high-end and low-end product. When a chip is new, the manufacturing process probably legitimately creates a small yield of faster parts and a high yield of slower parts. As the chip matures, more high-end chips are created. It is possible that if "too many" high-end chips are produced to meet demand, some may be marked at the lower speed to fill orders. Furthermore, sometimes dedicated production lines are used to produce chips of different speeds, but they are produced at rates not matching demand forecasts and may be marked at a lower speed. These chips of course would be easily "overclockable" because they were never marked at their full potential to begin with. The problem, of course, is that it is virtually impossible to figure out which chips were underrated! Still, a chip is generally more overclockable when it is the millionth off the production line than the first.

The latest craze is overclocking the system bus. More accurately, this is overclocking the system chipset and expansion cards. This is made possible because recently, motherboard manufacturers have started putting non-standard bus speed settings on their motherboards, allowing you to exceed the speed rating of the chipset.

Origins of Overclocking

Overclocking is popular today in large part due to the fact that modern PC circuitry makes it easy to do. You have motherboards with variable clock speeds on them and processors that respond to signals from the motherboard telling them how fast to run. It wasn't always this way, but overclocking on PCs has in fact been done for over 10 years. On other small microcomputers it goes back over 20 years!

On the PC, overclocking probably goes back to the original IBM AT, which used the Intel 80286 processor. There were two versions of this original system, running at either 6 or 8 MHz (later systems expanded the speed range of the 286 much higher). PC users who wanted more power realized that it was possible to convert the 6 MHz system to 8 MHz by replacing the 6 MHz clock crystal with an 8 MHz one. Like today's overclocking, sometimes this worked, sometimes it didn't, and sometimes it seemed to work but caused "software problems".

I have talked with some serious hardware hackers, guys who were building their own PCs from circuit boards before the PC was even a glimmer in IBM's eye. Apparently the Z80 processor was overclocked by some enterprising hardware experimenters back in the 1970s. This was done in a way similarly to how it was done on the 286, by changing the frequency of the oscillator circuit that drove the CPU clock. Overclockers would experiment with tuning and adjusting the oscillator to precisely control the speed of the machine in a way that cannot be done with modern hardware.

Modern PCs use neither an adjustable oscillator nor a fixed-speed clock crystal; they employ a precision-controlled, variable-speed clock circuit. A single motherboard can typically run at any of several different speeds, depending on how it is configured. This is probably the key step that really allowed overclocking to become popular, because it became much easier to change the frequency of the motherboard--there was no need to tinker with oscillator circuits, and no specialty hardware knowledge was required to overclock.

Who Overclocks?

It's pretty difficult to pinpoint exactly who the overclockers are, but they do tend in my experience to fit a pretty specific profile in most cases. They come from many different walks of life, but tend of course to be quite technically oriented, since this is obviously something that requires some technical skill. However, there are also some relative PC newcomers who overclock (usually based on the advice of someone who's been doing it for a while). Many overclockers are PC hobbyists, although many hobbyists don't overclock (like myself.)

The best analogy for overclockers that I can find outside the computer world is to compare them to car hobbyists. There are those who buy a car because they need a car; they care about performance, but it isn't the most important thing in the world to them. They aren't eager to sacrifice the reliability or safety of the car, or risk its warranty, to make it accelerate a bit faster. Then there are car enthusiasts, the hot-rodders, for whom tweaking the car to get it to maximum performance is very important, and something they consider fun and educational.

I find the same thing to be true of PC overclocking, in many ways. Those who advocate overclocking tend to be "PC hot-rodders", for whom getting the PC running as fast as possible is a hobby, a challenge, even an end itself instead of a means to an end. In fact, I sometimes think that many people overclock just so they can post to U***** and respond to ******s showing that they got their Pentium II to run at some incredible speed. :^) I think this is fine, but I think also that telling everyone to "go ahead, overclock your PC" makes about as much sense as telling everyone that they should start tinkering with their car's engine to make it accelerate faster. It only makes sense for some people.

Overclocking Risks and Rewards

Most of the controversy surrounding overclocking is related to the risk-reward issue: what is the real benefit of overclocking, and what is the true cost? This section takes a look at these issues in what I hope is a reasonably objective manner.

Overclocking is inherently risky because in doing so you are attempting to operate your hardware in a way that it was not designed to work. Circuit timing in a PC is very delicate in some cases, and you can cause very subtle problems by tinkering with it. In the sections below I try to look more specifically at what risks there are with overclocking.

Benefits of Overclocking the Processor

There's only one benefit to overclocking the processor, but it's a big one: you increase the speed of the processor, one of the most important devices in the PC for performance purposes. However, you must qualify this in modern PCs by realizing that the processor is only one factor in overall system performance. Even though 333 is 25% larger than 266, a Pentium II 333 system is definitely not 25% faster than a Pentium II 266 system for almost every task. The reason is that the processor is running much faster than the rest of the PC even at 266 MHz, so much of the extra speed of the 333 is wasted waiting for the memory or other components. This is explained in detail here.

Also you must realize that small improvements in performance are not noticeable to the average person. A speed increase of 8% may show up in your benchmarks, but it's not going to have any real-world effect on anyone other than someone doing serious, hours-long number crunching (and this sort of person can't afford the risks inherent in overclocking anyway). Most users cannot perceive any practical "feels faster" difference between 166 and 200 MHz processors of the same type, for example.

Risks of Overclocking the Processor!!!

There are definite risks that you are taking when you decide to overclock your system processor. There is much debate over what the risks are, ranging from "don't worry, be happy" attitudes from many hackers to those who think overclocking is very dangerous (I guess I'm close to being in that category, although I think it is reasonable in some circumstances). I hope to list here the dangers but with a reasonable indication of how likely they are, and really I don't think I'm going off the deep end with any of this stuff.

Here are the possible outcomes you can expect when you overclock your processor. These apply to raising the clock speed of the processor only, if you are changing the system bus speed above its nominal rating you will need to read here as well.

* Success: The processor may overclock perfectly, and run stably for many years to come. There are thousands of people who have done this, and I am certainly not going to deny it. This is the best case outcome.
* Immediate Destruction: It is possible to totally destroy a processor by attempting to overclock it. By destruction, I mean that the processor will not boot at the higher speed, and when returned to its normal speed, will continue to not function. This is basically the worst case outcome. This sort of permanent failure is very rare, but it does happen. It is made more likely by using inadequate cooling, and also by being ridiculously aggressive in how far you try to overclock (i.e., trying to run a Pentium 75 at 166 MHz.)
* Non-Functionality: The processor may not work at the new speed, but may work fine when returned to its original speed. This is a fairly common outcome when overclocking, and in most cases the processor will not be any the worse for wear.
* System Instability: The processor may boot at the new speed, but you may see the system behave strangely. Random hard lockups, parity errors, resource conflicts, strange hard disk problems, beeping, application crashes and Windows refusing to boot are just the tip of the iceberg. Particularly insidious are the overclocks that work almost perfectly, because that occasional crash may be due to your operating system, but it may be due to that overclocked chip also.
* Data Loss: It is very possible to lose data as a result of overclocking. If the processor is not functioning properly, you risk potentially damaging the structures of your hard disk's file system. It is also not uncommon for the Windows registry files to become corrupted, requiring a complete Windows reinstall. Needless to say, a full backup before overclocking is a wise move.
* Electromigration: When the processor is run at a speed that is higher than it is supposed to be run at, there is a chance that the internal components in the processor may break down over time. The internal features of a CPU are sized in the range of microns. It is possible that when the processor is stressed by running at too high a frequency, along with the extra heat that overclocking incurs, that the actual metal lines inside the processor may form shorts or opens and damage the processor over a period of time. How likely this is to happen, and how long it takes is really not known. The system may work fine for a while and then suddenly stop working.

In addition to the above, you should realize that overclocking a processor will reduce its serviceable lifetime. How long? Nobody can really say for sure, because nobody really knows how long a processor will last without overclocking. Controlling heat is a big part of this equation. When you see people on the 'net saying things like "without overclocking the chip would last 10 years and with overclocking it will last 5 years, so what do I care because I get a new chip every 2 years", just remember that they really have no way of knowing that they are reducing the CPU's lifespan by only 50%--it could be 90%. (And I don't know about you, but even when I upgrade, I don't throw out my old equipment if it still works...)

Also consider that hardware is not static; it ages, it changes over time--and it degrades over time. Even if overclocking works today, it may be working because you are just within the limits of what the system can handle. This doesn't mean that in six months or a year, changes in the hardware due to aging, heat or other stress factors won't cause failures or strange behavior to crop up.

I repeat, i did not write this whole tutorial...it is a collection of some of the best overclocking tips, and guides i have see/used over the years...ENJOY..BOBO

Part 2

this is one of my favorite guides to overclock a64's...and oh yeah...u can also use it overclock ur opterons...trust me it worked well with my 165...XD

Overclocking the 754 / 939 Platform

Anyone serious about PC gaming knows that the current king of CPUs is the AMD Athlon 64. Since its introduction in 2003, it has provided phenomenal performance, at much lower clock speeds than its Intel competitors. The Athlon 64 platform has brought many new features to the table and with these new features comes many new overclocking challenges. The purpose of this guide is to provide both theoretical insight into the 'art' of Athlon 64 overclocking, and to provide hands-on examples to assist you in your endeavours. There are numerous overclocking guides available online, but I hope that this guide will present a unique and fresh approach to a commonly misunderstood practice. The information I will present is an accumulation of knowledge that I have obtained over the past five years as a hardware and overclocking enthusiast. There is no clearly defined 'proper' way to overclock, but the theory and logical procedures that I outline will help you to avoid many otherwise inevitable headaches and frustrations.

This guide assumes some knowledge of computer hardware and software. However, it should be thorough enough for just about anyone to follow along and understand.

I will use the term 'Athlon 64' or 'A64' during the article quite frequently, but for all intents and purposes, any processor operating on the socket 754/939 platform is within the scope of this article. This includes, but is not limited to 'Athlon x2', 'Sempron/Sempron 64', 'Opteron 939' and 'Mobile Athlon 64' processors. The socket 940 platform is not within the scope of this article, however much of the theory still applies.
Guide Overview

Intro [1]

* Hyper Transport
* Integrated Memory Controllers
* Cool n' Quiet

Theory [2]

* Power, Amperage and Voltage 101
* Heat and Cooling
* How to Overclock an A64 (in a nutshell)
* Overclocking the HTT bus, is it useful?
* A64 Mathematics
* A64 CPU Multipliers
* CMOS, Bus Locking, Memory Modules and Timings
* CPU Stepping Codes, CPU Selection, Mobile Athlon 64, and Hardware

Overclocking Tools [3]

Step 1: Getting Started [4]

* Qualify System for Overclocking
* Testing Configuration

Step 2: Finding the Maximum CPU Clock

* Finding the Maximum CPU Clock Speed
* Longer-term stability testing

Step 3: Finding the Maximum Memory Clock at the Best Possible Timings. [5]

* Knowing Your Memory
* Stability in the Operating System: Painting a very different picture

Step 4: Balancing Memory and CPU Clock [6]

* Selecting a safe maximum CPU and Memory clock
* Long-term Stability Testing

Benchmarking

Conclusion

Intro [1]

Hyper Transport

When AMD designed the Athlon 64, it was a big step in a new direction that really set it apart from its predecessors. The 64-bit instruction set was certainly its most unique feature. However, there are numerous other features, which are relevant to overclocking that we'll discuss. New acronyms like LDT, IMC and HTT have scared many 'old school' overclockers. But, once you read a bit about these new features, you'll realize that there is nothing daunting about these new platforms and you'll be ready to get down to business.

AMD's A64 platforms have abolished the 'Front Side Bus'. The 'Front Side Bus' was essentially a data bus that carried data to and from system components and the CPU (usually by connecting the CPU to the north and southbridge chipsets). These chipsets provide connections to other buses, such as the AGP and PCI bus, and many other system components. All current Intel platforms, and pre-A64 AMD chips follow this basic model.

AMD decided to do things a little differently with the A64, and adopted 'Hyper Transport Technology'. Hyper Transport is a high-bandwith, low latency computer bus that replaces the aging FSB. The Hyper Transport bus does essentially the same thing as the FSB, only much faster. Many people find themselves still calling it FSB, but for the sake of correctness, we'll call it the HTT bus.

There is a common misconception that Hyper Transport Technology is a proprietary AMD technology. HTT was developed by the 'HyperTransport Technology Consortium'. Hyper Transport, sometimes called LDT (Lightning Data Transport) has been used by many vendors, including nVidia and Cisco Systems. You may recall that nVidia used HTT to provide high bandwidth, low latency communication between the north and southbridge chipsets in their older socket A 'nforce' platforms.

The Hyper Transport bus operates using a multiplier system to derive its overall speed. The 'base' or lowest HTT frequency that the HTT Consortium defined is 200MHz. The overall operating clock speed that the HTT operates at is simply a multiple of that 200MHz base or 'reference' frequency. Many other clock frequencies are also derived from this 200MHz reference clock, such as CPU clock speed. Most Socket 754 A64s, for example, operate at an HTT speed of 800MHz. A clock multiplier of 4x was used to obtain this. So 200x8 = 800MHz. You may be asking why AMD lists an HTT speed of 1600MHz in the specifications for these processors. HTT is a 'double pumped' or 'double data rate' technology, much like DDR RAM. So, simply double the final result. 200x8 = 800MHz x 2 = 1600MHz. I'll get more into A64 Mathematics later on.

Integrated Memory Controller (IMC)

The primary function of the 'Northbridge' in older 'pre-A64' platforms was to provide an interface between the system memory and the CPU. You may notice that most A64 mainboards only have one chipset, as opposed to the north/south pair seen on older Socket A boards. All memory read/write requests had to traverse the FSB before arriving at the northbridge.

AMD decided to incorporate an 'on-die' memory controller in all Athlon 64/Sempron 754 models. This memory controller operates at the same clock speed as the processor, which results in very low access times to main memory. Since this IMC is on-die, there is no external data bus that memory traffic needs to traverse either. This on-die memory controller has proven to make the A64 one of the best gaming processors available. Low memory latency often equates to higher numbers of frames per second during gaming. The IMC also poses some challenges and benefits when overclocking, and we'll see why in later sections.

Much like the late Socket A platforms, the A64 is designed to use PC3200 DDR memory, which has a base speed of 200MHz (400MHz double data rate). Memory dividers can be used for slower PC2700/PC2100 memory without having to reduce the reference clock speed. There will be more discussion surrounding memory modules and dividers ahead.

Cool 'n' Quiet

Cool 'n' Quiet is another interesting feature that AMD has incorporated into its latest platforms. It essentially throttles down the processor to a fraction of its operating frequency by using lower multipliers and decreasing the core voltage when idle. This equates to much lower temperatures and power consumption. When the CPU load increases so does the clock speed and vcore. Cool 'n' Quiet is a feature that most overclockers disable. Having the processor automatically decrease voltage when running clock speeds out of spec can cause instant instabilities and other issues. Having more predictable behaviour from the CPU is very beneficial when looking for high overclocks. Cool 'n' Quiet technology, although not generally used by overclockers, is a blessing in disguise. We'll see why later.

on to part3....

N00B intro to overclocking...

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