CPU Over Clocking

Date Article Written: July 23, 2000
Written By: Mark Torres

So you have a need for speed huh? You could go out and buy a new processor, or you could simply over clock your existing one. Well that is all well and good, once you consider a few things. One, over clocking your processor creates more heat, which is bad for the chip. Two, over clocking will more than likely void any kind of warranty you have on your hardware, not just your CPU but also your motherboard. You also have to think about the rest of your system. Can your RAM and motherboard handle a higher Front Side Bus, and what about everything else, like the PCI and AGP bus speeds, they increase too. All and all, you just need to think before you act, and remember you're not just changing one thing, you're affecting your whole system in one way or another, and you must be sure you can computer can handle it. Now with all this in mind lets get started.

You need to understand how your CPU speed is determined before you can boost it up. Two things determine how fast your CPU speed is. The Front Side Bus (FSB) is the speed in MHZ that your computer communicates with the rest of the system and your clock multiplier. To get your total CPU speed, you multiply the FSB times the clock multiplier, which equals CPU speed. For example, a Celeron 300a has a 66mhz bus speed, and a 4.5 multiplier. 66 x 4.5 = 300. 300 MHZ is my CPU speed. So to increase the actual speed of the system we have to change on of the two variables. The multiplier can't be changed, so we have to change the Front Side Bus.

Changing the front side bus is pretty easy. Enter your computers setup program, or BIOS. To get there, reboot your computer and look for something that says "Press F2 to enter SETUP" or "Press DEL to enter SETUP." Press the key that applies, and you should end up in your BIOS. Once in, look around until you find an option that lets you change your FSB, System Bus or Clock Speed. They are all the same thing, and should be between 66 and 133mhz. So with the capability of your RAM and Motherboard in mind, increase your speed, and multiply it by the multiplier to get you new CPU speed. To get your multiplier, if it is not listed in your BIOS under the FSB, I would go to the manufacturer's web site who made my CPU and look it up there.

The highlighted option in the picture is an example of what the FSB setting looks like in the BIOS.

WAIT!!! I don't have that option in my BIOS. Ah, no big deal, that just means you have jumpers on your motherboard. A jumper is a small plastic clip that slides over two or more metal pins that close an open circuit to set and option, or complete a task. Almost like a switch. Open your case and look on the motherboard for jumpers that let you set a different FSB or even a multiplier. Depending on the maker of the board, you can change one or the other, both or neither. To get a full list of what jumpers do what, check out the manufacture's web site, or look at the little white writing on the motherboard. If you don't find jumpers, and cant configure your BIOS to that extent then it is possible that you can't over clock your CPU. Intel motherboards are known for not letting you over clock where on the other hand EPOX makes probably one of the most configurable boards on the market. It just depends what kind of hardware you have.

Of course there is one more option, you can download a program known as SoftFSB from H.Oda. (www.h-oda.com) This nifty windows program allows you to change the FSB in real time, and supports several boards that wouldn't allow you to overclock otherwise. It also allows more FSB speeds on some boards than you could achieve using the BIOS or by jumpers. However you must realize that this program isn't a permanent change to your system, and it must be run every time windows starts up, fortunately there is an option in the program to automatically load on windows startup.

For Mark's next article, he is going to write on keeping your over clocked CPU cool...

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