Overclocking guide

Well, there are a number of different considerations to make when beginning the project. The first is cooling. Traditionally, most systems are cooled by air. This is a standard and cost-effective solution, although it can be noisy. However good case flow is very important when embarking on an overclock. This will help keep the CPU, RAM modules and graphics card as cool as can be, which is important as these are the components that will be overclocked.

Once you are satisfied that you have adequate cooling, you may begin. For reference, the CPU temperatures will be around 40C or less if you have reasonable cooling. It's still possible to overclock with higher temperatures but you overclocking potential will be reduced. It's generally not a good idea to try to overclock if your temperatures are much above 50C. Bear in mind that all components get hotter as more processing load is placed upon them.

Some motherboards don't have any overclocking features but these tend to be Intel boards supplied by system builders. More-or-less any board you buy yourself in the shops will have overclocking features, although it's best to look at reviews to see which board is right for you if you choose to buy ityourself.

The art of overclocking typically begins in the BIOS (some motherboards control certain overclocking features by means of jumper settings but this is very uncommon). Usually the CPU multiplier, FSB/HT frequency and memory dividers can be set in the BIOS. The clock speed of the FSB/HT connection tends to dictate the speeds of all the other components. Memory will perform best when running synchronously with the FSB i.e. with a 1:1 ratio (therefore if the FSB is 200MHz, the memory will run at 200MHz). This can be changed but is best left alone generally. However, the AMD Athlon 64 and Sempron S754 processors all feature an on-die memory controller, so in this case it may be preferable to change the memory divider to allow for a higher CPU overclock.

So to summarise, overclocking a computer is generally done using the following steps:

* Ensure adequate cooling
* Increase FSB/HT frequency (only small steps at a time)
* Check system stability using a stress utility (Prime95 is commonly used for this purpose)
* Repeat until the system fails the Prime 95 stress test and then roll back the FSB/HT frequency a few megahurtz from the first point at which you noticed instability
Those above steps will overclock CPU and RAM. Graphics cards can be overclocked using special windows tools such as RivaTuner.

Tips and Tricks:

As well as frequencies, voltages can also be controlled from the BIOS. To increase your overclockability you can try increasing the voltages of CPU and memory, but you have to make sure that your cooling system can handle it first. It's also a bad idea to overvolt by more than ~10% as this will reduce the life span of the component in question.

The final note is that no two components have the same overclocking potential. In the past certain CPU batches or core revisions (as identified by the markings on the CPU itself) have been identified as good overclockers such as the current low-end AMD Athlon 64 based on the Venice core. Low clocked Pentium 4s are also well known for their overclocking potential. But just because your friend reached 2.6GHz, it doesn't mean that you will. It's luck of the draw at the end of the day.

Happy hunting!
EDIT 2: Water Cooling - It will always improve the overclockability of a given system since it is more efficient at removing heat from the CPU (and any other component you wish to cool with it e.g. GPU and Northbridge), thus reducing idle/load temperatures. Personally, I'm against it because it's more difficult to set up and maintain, and costs quite a bit more for a disproportionate gain of OC potential. That said it's a much quieter solution than air, so it has its pros and cons.

1.65V through an Athlon 64 using air cooling sounds insane to me. If you do try it make sure you have VERY good ventilation in there. Personally, I think 1.55V is enough. I doubt you'd squeeze much more than maybe 100MHz+/- by going higher so it's probably not worth the hassle.

http://www.insanetek.com/review.php?id=10 a64
http://www.overclock.net/showthread.php?t=1567 p4
http://www.overclockers.com/ general ocing
http://www.xtremesystems.org/forums/
http://files.extremeoverclocking.com/file.php?f=36 SuperPi
http://www.futuremark.com/ -benchmarking
http://downloads.guru3d.com/download.php?det=673
http://files.extremeoverclocking.com/file.php?f=103 Prime 95
http://www.guru3d.com/rivatuner/ NVidia Ocer
http://www.techpowerup.com/atitool/ ATI ocer
http://www.cpuid.org/cpuz.php CPUZ best program ever
http://www.extreme.outervision.com/index.jsp PSU calculator
Credit goes to Xbitlabs.com I just got most of the links for you guys..

// chet