After the above information has been compiled, it should be quite easy to rate the ability of your motherboard to handle the overclocking job ahead. The best scenario is having a motherboard that allows a full complement of voltage tweaks, along with a wide selection of FSB speeds. Even if the FSB options aren't as robust as you would like, the voltage control is the key element. Motherboards that do not offer any form of voltage tweaking at all are likely to offer the lowest overclocking return. The only way around this limitation is by using a Socket CPU/Slocket adapter combo with a Slot 1 motherboard, or an Athlon with a Goldfinger overclocking device. Socketed processors will always require some form of multiplier and voltage control directly from the motherboard itself.

The above analysis is important both in terms of knowing the motherboard's capabilities as well as having realistic overclocking expectations. If you own, or intend to purchase, a motherboard offering full core voltage control and FSB increases in 1 MHz increments then you will have an excellent chance of reaching the CPU's maximum speed. On the other hand, a motherboard with little or no voltage control and a small set of FSB options will have less overclocking success, and the target should be lowered to a more realistic level. Regardless of the overclocking potential of the CPU, the actual overclocked results will either be limited or enhanced by the motherboard itself. The only exception to this is with the AMD Athlon, where the use of an external Goldfinger overclocking device is the key element.

When increasing the FSB beyond the CPU's default speed, it is important to understand how this can affect your system. Depending on the motherboard chipset, some or all of the 66, 100 or 133 MHz settings will be available using standard AGP and PCI dividers. With the Intel 815E or Apollo Pro 133A, this would mean that when running a CPU on the 66, 100 or 133 MHz FSB, that the system would maintain standard 66 MHz AGP and 33 MHz PCI speeds. On older chipsets such as the Intel BX, AMD 750/751 or VIA KX/KT133, this would mean the 100 MHz FSB would be the maximum speed where AGP and PCI speeds would remain standard.

Where this really comes into play is when using a FSB that results in non-standard AGP and PCI speeds. Overclocking most 66 MHz Celerons to the 75 or 83 MHz FSB is usually pretty easy, but it can result in some other system problems. When running on an 83 MHz FSB, the AGP speed is also 83 MHz and the PCI speed is over 41 MHz. These speeds can result in problems with some AGP and PCI cards, and many IDE hard drives will display errors when using a high PCI speed. As a basic rule, speeds of 66-99, 100-132 and 133+ MHz FSB will use the AGP and PCI divider of the lowest default FSB speed in the range. There are exceptions to this rule, and certain motherboards offer higher AGP/PCI dividers at FSB speeds such as 90-99 MHz or 124-132 MHz, which will result in a lower than standard AGP and PCI speed. Running on a 60 MHz AGP and 30 MHz PCI speed may slow your overall system performance just a bit, but it is preferable to running seriously over spec.

The overclocked FSB also has an effect on your system memory, and depending on its quality, may contribute to system instability. Your system FSB is also by default, the speed of your system memory as well. This means is that when using PC100 memory on an overclocked 120 MHz FSB, the memory may not be able to keep up to the higher 120 MHz memory speed. Some motherboard chipsets, such as the VIA products, may allow memory speed to be increased or decreased relative to the system FSB. This can come in handy when overclocking, but those with older chipsets and memory should keep an eye out for memory speed issues, and possibly lower the RAS and CAS BIOS settings accordingly.