OVERCLOCKING is a very famous thing between Computer freaks/enthusiasts. It gives more juice from your Rig(computer). Overclocking is basically a technique to run your components outside the company/product specifications. This will also void your warranty so be carefull while playing with them.
Processors
I am gonna start with the processors. There are two major company in the market AMD and INTEL. I personally in favour of AMD, therefore I am using an AMD processor in this example. IN AMD there are many different models to choose from, however I am going to use their 32 bit Ahtlon XP 2500+ (based upon the Barton core). This does not mean that you cannot overclock any other processor, this one is just the most flexible in my opinion. Earlier Bartons have unlocked multiplier but now they are locked so, you can't change the multiplier without any modifications to the processor. While I am just using the steps below as a referrence, these techniques can be applied to most computers/systems available today.
Motherboards
Now the motherboard, I think the best chipsets for AMD 32 bit processors are the nVidia nForce2 chipsets. All others like Via, etc. are equally good. However, again I am just using the nForce2 chipset for this example.
There is something that is very necessary in overclocking and that is patience! You have to slowly take each and every step to minimize damage and check for stability. It is also important to benchmark your system. So, it also takes a lot of time for perfect overclocking. First thing you need to know is clearing your CMOS (a.k.a. BIOS) beacause every time your system failed reboot you have to clear it and again start from where you stoped. Also get the list of beep codes for your Bios. This may help you detect which of the components is creating a problem. The first thing is FSB (Front Side Bus) speed at which motherboard communicates with various component like CPU and RAM. There is a CPU FSB sometime called as CPU External frequency, you can increase your CPU FSB slowly (from bios or any overclocking software like nTune from nVidia) and check your system (double check that your PCI and AGP clockes are locked ie. they not change with the FSB check your motherboards manual for this). Sometimes motherboard manufactures give the Bios a very limited setting for FSB. For example, the ASUS A7N8X deluxe has a maximum FSB given of 215Mhz but you can download a new bios meant for overclocking from the internet. These BIOS' are often referred to as an UBER bios where there with added features specifically for overclocking such as a maximum FSB of 300Mhz.
Memory
To reach the kinds of speeds above, you should purchase good memory modules like Corsair or OCZ. Beacause when you increase CPU FSB, RAM FSB also gets increased. With normal memories you can go to a maximum of 210 to 215 Mhz with some relaxed memory timings. The main memory timings are Cycle Time (tRAS), Ras to Cas Delay (RCD), Ras Precharge (RP), and Cas Latency (CL). You have to optimize these for your motherboard and then benchmark it with sandra(or any other your preference). You should also check for memory bandwidth and determine which settings give maximum memory bandwidth.
CPU Multiplier
Next thing to cover is the CPU frequency multiplier. This is a number which is multiplied with FSB to get the actual CPU frequency. Like a processor having FSB 200Mhz and multiplier of 11 will run at 2200Mhz. Some CPU's have locked multipliers so to unlock mulitipliers use google and search the net.
Core Voltage (a.k.a. Vcore)
You can increase your Vcore and get some increase in speeds, However this can be dangerous for your system because more voltage means more current running through the processor transistors and could lead to premature failure. Furthermore, more speed means more heat so more cooling may be necessary.
Mobile CPUs
Some people prefer Mobile processors (Laptop processors) because they take less voltage and generate less heat, so there is more room for overclock. As mobile bartons works on 1.45v and destop bartons at 1.65v. I have seen 2500+ barton which has a 166Mhz FSB work fine at 250Mhz Fsb. Always have a motherboard monitering program installed on ur system and fix the theshold limits properly. This way you can't go wrong with your overclocking. Many argue this next point, but some overclocking can be safe if done properly. However caution should be taken as you can fry a CPU.
Once you have a safe, stable overclock note your CPU and Motherboard temparature at idle and full load. If these are high, then you should look into getter a better cooling solution and case ventilation. For case ventilation put two 80mm fans for inlet and 2 80mm fans for outlet. And also try to get bigger case as these provide better in ventilation. For CPU cooling you can go for either air or water. Water coooling is good but expensive and does provide additional risk if done incorrectly, air cooling is typically cheaper.
DIMM Voltage
Another voltage setting is vdimm (DDR voltage level). You can also increase this to get better performance. If after a overclock, memory is becoming a performance bottelneck and/or stopping the system from booting then you can try increasing the memory voltage. This is a bit risky so I don't prefer this. First check the maximum voltage level for your module then do the increase. Because of the increase in voltage, the memory chips generate more heat. Therefore, memories with heatsinks are more suitable for this type of overclocking.
Another useful feature I have seen in motherboard I like to talk about is RAM speed lock function. MSI K8N has this feature, in this, the RAM speed can be locked and then which means the CPU FSB and RAM FSB each has their own ratio. The default case these are typically 1:1. If our CPU FSB is 200Mhz then RAM FSB is also 200Mhz but while overclocking I have found that I can't go beyond 215Mhz beacause of memory limitations. In this case, locking the RAM FSB to 166 might make it possible to increase the CPU FSB thereby gaining better performance. Such a case is useful for those that do a lot of CPU intensive tasks like audio or video encoding etc.
At last I can say that in my opinion, overcloking is a safe way to increase the performance of the CPU. HAPPY OVERCLOCKING
Some good links on overclocking
AMD64
LAPTOP
Which PSU
Prime95 Stress Testing
Tomshardware CPU Chart
If i missed something here please let me know ......
Rahul
Processors
I am gonna start with the processors. There are two major company in the market AMD and INTEL. I personally in favour of AMD, therefore I am using an AMD processor in this example. IN AMD there are many different models to choose from, however I am going to use their 32 bit Ahtlon XP 2500+ (based upon the Barton core). This does not mean that you cannot overclock any other processor, this one is just the most flexible in my opinion. Earlier Bartons have unlocked multiplier but now they are locked so, you can't change the multiplier without any modifications to the processor. While I am just using the steps below as a referrence, these techniques can be applied to most computers/systems available today.
Motherboards
Now the motherboard, I think the best chipsets for AMD 32 bit processors are the nVidia nForce2 chipsets. All others like Via, etc. are equally good. However, again I am just using the nForce2 chipset for this example.
There is something that is very necessary in overclocking and that is patience! You have to slowly take each and every step to minimize damage and check for stability. It is also important to benchmark your system. So, it also takes a lot of time for perfect overclocking. First thing you need to know is clearing your CMOS (a.k.a. BIOS) beacause every time your system failed reboot you have to clear it and again start from where you stoped. Also get the list of beep codes for your Bios. This may help you detect which of the components is creating a problem. The first thing is FSB (Front Side Bus) speed at which motherboard communicates with various component like CPU and RAM. There is a CPU FSB sometime called as CPU External frequency, you can increase your CPU FSB slowly (from bios or any overclocking software like nTune from nVidia) and check your system (double check that your PCI and AGP clockes are locked ie. they not change with the FSB check your motherboards manual for this). Sometimes motherboard manufactures give the Bios a very limited setting for FSB. For example, the ASUS A7N8X deluxe has a maximum FSB given of 215Mhz but you can download a new bios meant for overclocking from the internet. These BIOS' are often referred to as an UBER bios where there with added features specifically for overclocking such as a maximum FSB of 300Mhz.
Memory
To reach the kinds of speeds above, you should purchase good memory modules like Corsair or OCZ. Beacause when you increase CPU FSB, RAM FSB also gets increased. With normal memories you can go to a maximum of 210 to 215 Mhz with some relaxed memory timings. The main memory timings are Cycle Time (tRAS), Ras to Cas Delay (RCD), Ras Precharge (RP), and Cas Latency (CL). You have to optimize these for your motherboard and then benchmark it with sandra(or any other your preference). You should also check for memory bandwidth and determine which settings give maximum memory bandwidth.
CPU Multiplier
Next thing to cover is the CPU frequency multiplier. This is a number which is multiplied with FSB to get the actual CPU frequency. Like a processor having FSB 200Mhz and multiplier of 11 will run at 2200Mhz. Some CPU's have locked multipliers so to unlock mulitipliers use google and search the net.
Core Voltage (a.k.a. Vcore)
You can increase your Vcore and get some increase in speeds, However this can be dangerous for your system because more voltage means more current running through the processor transistors and could lead to premature failure. Furthermore, more speed means more heat so more cooling may be necessary.
Mobile CPUs
Some people prefer Mobile processors (Laptop processors) because they take less voltage and generate less heat, so there is more room for overclock. As mobile bartons works on 1.45v and destop bartons at 1.65v. I have seen 2500+ barton which has a 166Mhz FSB work fine at 250Mhz Fsb. Always have a motherboard monitering program installed on ur system and fix the theshold limits properly. This way you can't go wrong with your overclocking. Many argue this next point, but some overclocking can be safe if done properly. However caution should be taken as you can fry a CPU.
Once you have a safe, stable overclock note your CPU and Motherboard temparature at idle and full load. If these are high, then you should look into getter a better cooling solution and case ventilation. For case ventilation put two 80mm fans for inlet and 2 80mm fans for outlet. And also try to get bigger case as these provide better in ventilation. For CPU cooling you can go for either air or water. Water coooling is good but expensive and does provide additional risk if done incorrectly, air cooling is typically cheaper.
DIMM Voltage
Another voltage setting is vdimm (DDR voltage level). You can also increase this to get better performance. If after a overclock, memory is becoming a performance bottelneck and/or stopping the system from booting then you can try increasing the memory voltage. This is a bit risky so I don't prefer this. First check the maximum voltage level for your module then do the increase. Because of the increase in voltage, the memory chips generate more heat. Therefore, memories with heatsinks are more suitable for this type of overclocking.
Another useful feature I have seen in motherboard I like to talk about is RAM speed lock function. MSI K8N has this feature, in this, the RAM speed can be locked and then which means the CPU FSB and RAM FSB each has their own ratio. The default case these are typically 1:1. If our CPU FSB is 200Mhz then RAM FSB is also 200Mhz but while overclocking I have found that I can't go beyond 215Mhz beacause of memory limitations. In this case, locking the RAM FSB to 166 might make it possible to increase the CPU FSB thereby gaining better performance. Such a case is useful for those that do a lot of CPU intensive tasks like audio or video encoding etc.
At last I can say that in my opinion, overcloking is a safe way to increase the performance of the CPU. HAPPY OVERCLOCKING
Some good links on overclocking
AMD64
LAPTOP
Which PSU
Prime95 Stress Testing
Tomshardware CPU Chart
If i missed something here please let me know ......
Rahul
