!!! I am godzilla, you are Japan!!! (tehschkott) wrote in 933k,
!!! I am godzilla, you are Japan!!!

warning, boredom alert... notes on overclocking and my summary for my benefit


i'm detailing this so it makes sense to me. i guess summarizing what i've learned so i can
make sense of it and find flaws in the logic or my understanding of it. this is purely an
academic exercise... i'm just running numbers here. it's undecided as to whether or not
i actually plan to do it, but i probably will do a little bit of "tuning", if only just to see.

CPU's are traditionally rated to process data at certain speeds, due in large part to the amount of heat they generate. (CPU will operate at "X" MHz and generate "X"degrees of heat before it fries and becomes unstable). The cooler you keep your CPU, the more processing power you can get out of your processor. Doing this is called "overclocking".

Overclocking is done in three seperate ways. Adjusting the Clock Multiplier, adjusting the Bus Speed, or adjusting both. Adjusting both is the best way.

The Clock Multiplier is used to determine how much faster the CPU will operate than the bus speed. Basically you're telling your CPU how hard to work. in my case (10 x 133mhz) it means that the CPU is going to operate 10 times faster then a bus speed of 133mhz. The trade-off is that by working your CPU harder it generates more heat.

The Bus is the skein in which both the CPU and the RAM communicate with one another and the rest of the computer. The Bus Speed is how fast they're able to communicate. By adjusting the Bus Speed you are telling the rest of the computer (other then the CPU) how quickly to communicate with one another. The Bus Speed would be best described as a water pipe. By increasing the Bus Speed, you are using a larger pipe to move water in so you're able to move more water and you are able to move it faster. The Bus Speed doesn't generate anything, it merely allows data to travel more quickly. The CPU however relies on the Bus to maintain a certain amount of resistance so the CPU doesn't go unchecked, overload and overheat. If the CPU is a water spigot, the Bus is the Nozzle of the garden hose to regulate the waterflow. Open the nozzle too far without adjusting the spigot will just cause the water to gush out and you'll run out of water... or in this case, if the bus speed is too great and your CPU isn't either turned down or has a super cooler on it, it'll overheat and fry.

The best way to overclock is by reducing the Clock Multiplier and increasing the Bus Speed equivalently so it still equals 1330 Mhz (1.33 Ghz). By doing so you increase the maximum output of the CPU AND increase the efficiency of your RAM by making better usage of the bus by 33%. To continue with the metaphor... it would be like garden hose and putting your thumb over the nozzle to make it squirt farther. it's the same amount of water coming out of it, but theres more power behind it, it moves faster, and you can control it better.

This is how it's done.

I'm going to use the system parameters that come with my system. They are as follows...

Motherboard = Abit KT7-A RAID (w/ Apollo VIA KT133-A chip set)
CPU = Athlon AMD 1.33 Ghz
RAM = 1024 megs (1.024 Gigs - 2x 512 Corsair PC133 DDR Cas 2)

The Motherboard has a standard 133Mhz Bus that can change anywhere between
100Mhz - 183Mhz. The minimum we will want to use is 133Mhz

The Clock Multiplier will adjust anywhere between 5x - 12.5. The minimum we will be able to use is 7.5x

The Default setting on this computer is 10 x 133Mhz (10 x 133Mhz = 1330 Mhz or 1.33Ghz)

the actual formula to find out what your system runs at depends on your CPU. This is what mine will run at. The easiest way to find out is to take your CPU rating in Megahertz, divide it by the bus speed of your system to find the multiplier.

The first thing that will need to happen is that there will need to be adequate cooling on the CPU. Anything we do from here on out is going to increase the operating temperature of the CPU. So there NEEDS to be a good heat sink on the CPU and sufficient cooling in the computer case itself or the CPU will fry itself. this problem is easily remedied with a good heat sink/ fan combination and a couple of good case fans for the most part. I can't stress this part enough. You cannot have enough cooling.

The thing to remember is that heat destroys or shortens the life of a CPU, not overclocking. Heat is going to be your worst enemy. If you provide sufficient cooling, everything should be fine. Heat is also the thing that creates instability. Parts heat up beyond their operational capacity, seize up and stop working/processing. We traditionally use air-cooled heat sinks to bleed-off heat that is generated by the CPU to keep it at an operational and stable temperature. If you provide better cooling you're actually not only lengthening the life of your CPU... you're broadening the efficiency parameters of your CPU so it is possible to work it "harder" with better results. In theory, if we used liquid cooled heat sinks (which can keep the CPU much cooler) it is possible to broaden those parameters even further allowing us even more processing power... i'm not that hard core though. air-cooling is a much more cost efficent, common, and simple and will more then meet my needs.

as long as you're careful to keep your CPU cool enough, you can take the above principles and take it a step further to "overclock" your system. Overclocking is nothing more then focusing or tuning your computer to operate at peak efficiency. Doing so requires more effort and attention/maintenance on the part of you, the user, in order to make it happen.

below, the first table is composed of multiples of 1.33Ghz (1330 Mhz). These alternate multiples are examples of settings that would be used to "tune" a 1.33 Ghz CPU system with a 133mhz bus to it's most efficient levels. Remember, the lower the Clock Multiplier and the higher the Bus Speed, the better the combination. At a traditional 10 x 133Mhz setting, the CPU has to work 10 times faster then the bus speed in order to operate at a 1.33Ghz level. That is the standard and that is whats normal but it's not what's most efficient. Whats better then that? 7.5 x 177Mhz. The CPU only has to work 7.5 times as fast to achive the same effect because the Bus Speeds have been increased. By increasing the Bus Speeds you also increase the productivity of the RAM in the same way. Basically both your RAM and your CPU are using the same skein to talk to one another and the rest of the computer with. If you open up the bus speed so your CPU doesn't have to work as hard, your RAM will also take advantage of the open bus settings and increase performance in the same way. The flood gates will have been opened so to speak and both will benefit. And RAM doesn't generate heat.

at the top is the standard setting. below it are more efficient settings.

clock multiplier
bus speed
CPU operation rating
10 x
133 MHz
1.33 Ghz
very basic.. standard
9.5 x
140 MHz
1.33 Ghz
9.0 x
147 MHz
1.33 Ghz
8.5 x
156 MHz
1.33 Ghz
8.0 x
166 MHz
1.33 Ghz
7.5 x
177 MHz
1.33 Ghz
optimal tuning config

by tuning your system in this manner, you will increase both the efficiency/capacity
of the CPU and the RAM by almost 33%. In this case the normal 1.33Ghz CPU will operate at an effective 1.76Ghz and the RAM, rated at 1.024 Gigs will operate at an effective 1.361 Gigs. In theory. In practice it probably won't go this high due to other factors (RAM speeds and so on) but you get the jist.

8.0 x
179 MHz
1.43 Ghz
notice that to raise the effecive rating by 100 mhz is half a multiplier and 3 Mhz with little or no difference in performance.

okay well that's it i guess. gotta annotate this shit somewhere don'cha know...

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