Overclocking a processor may damage it, proceed with care!
Overclocking a processor or the FSB (Front Side Bus) to gain an increase in
processor or FSB speed. Over the last couple of months I have had a lot of
inquires about 'overclocking'. So I think it is time I tried to explain this
phenomenon in Layman's terms.
First some technology about processors. Processors work by a change of
electrical polarity. In other words positive or negative, yes or no, on or off.
The electrical voltage present in a transistor is on, positive, or yes. The lack
of voltage is off, negative, or no. Now that is only part of the story, another
part is the frequency that the voltage changes, and we call that the speed!
Ah-ha, now we are getting somewhere. So there is a circuit on the mother board
that controls the frequency, it has a crystal, sometimes two or three, that sets
up the 'clock frequency' for the mother board and the processor. The processor
gets the frequency from this circuit, so does the FSB.
So we want to increase the speed of the processor and / or the FSB to get a
performance boost from the computer. Simple! Well yes and no. It is simple to do
but it is not a thing to do lightly, you could damage your processor, memory,
and motherboard. So think about it before you overclock your system.
As with all technology you should research the subject, do
not become knowledgeable, become an expert.
When the manufacture designs and produces a processor they go through a
testing stage. They know from experience approximately how fast the frequency of
processor is by the design. Then through this testing they find the minimum and
maximum clock speed of the given design. So when you buy your computer or build
your own you know the processor speed is x.x GHz. Normally processor speed it
rated 20% above minimum and 30% below maximum. These are general guidelines,
some processors may be at the safety limit of their heat tolerance when they
are produced. One I remember in particular was the original Celerons, the
486 33MHz Celerons could not be overclocked unless you wanted to buy another one
in a couple of weeks.
There are a couple of reasons why people overclock their systems. One is they
have the fastest processor available [been there, done that] or they can't
afford the fastest processor at the time [yup, me too!] or they are waiting for
the next generation and don't want to upgrade just yet [gee you guys know me!].
Scenario:
You have a processor and don't want to upgrade to the latest and greatest
because there is a new processor about to be released. So you say to yourself -'Self,
why not overclock this processor until the new one comes out?' So Self says 'Ya!
Why NOT? GO FOR IT!'
Well there is danger
Will Robinson! you could fry a whole bunch of stuff by not heading the warnings
about Overclocking!
Because the processor and memory work on voltage and amperage changes it
creates heat, sometimes lots of heat! An
increase of 0.012 volts (That is 0.012 volts)
will increase the heat out put of your processor by 10 degrees Fahrenheit - 5
degrees or so Celsius. So lets say you bump (increase) your processor speed by
500 MHz. How much heat would that produce above the normal operating temperature?
Unknown. Each processor has a set operating temperature that you will
have to find from the manufacture.
First thing you want to be sure of doing is
INCREASE the amount of
cooling that the motherboard and
processor get. This is fairly cheap and easy to do,
although may raise the noise level of the computer,
by adding fans. One or two will increase the cooling air moving through the
computer enough to lower the overall temperature by 10 to 30 degrees depending
on the temperature in the room where the computer is located. Next you will want
to increase the size of the heat sink, the
standard heat sink that comes with a processor is only good for an increase of 5
to 10%. If your processor is running at 115 degrees Fahrenheit then 10% would
only give you 11 degrees leeway. So you
need to increase the cooling capacity of the heat sink BEFORE you even consider
Overclocking the processor. You also need to know what the operating temperature
of the motherboard is before you do any changes.
Warning: Excessive heat will cause the materials
of the motherboard, processor, and memory to degrade faster.
So now you know that the processor's original clock speed is say 2.4 GHz, and
the temperature is about 127 degrees Fahrenheit, the motherboard is running at
about 95 degrees Fahrenheit. So lets bump that to 2.8 GHz and see what we get -
147 for the processor and 108 for the motherboard. That is about 20 degrees
Fahrenheit for 400 MHz speed. (these numbers are from my desktop that is an ASUS
P4B motherboard with a 2.4 GHz 533 FSB processor) I also have a larger heat sink
with a faster fan on the processor. There are five fans (not including the power
supply fan) in the system.
To find out the temperature range of your system you will have to research
the motherboard, processor, and memory from the manufacture. The ASUS
motherboard that I use (above example) states the maximum operating temperature
is 135 degrees Fahrenheit and the processor is 165 degrees Fahrenheit. So I am
pushing the heat factor by overclocking the system.
Every motherboard manufacture that produces a motherboard that can be
overclocked will have a chart for the processor and FSB. Be aware that the
processor and memory have to match,you can not
put a 533 FSB processor and 667 FSB memory on the same motherboard, it will not
run, in fact it will not power up! So you have a processor of say
3.0 GHz and a FSB of 800 MHz, you want to overclock it to say 3.6 or 3.8. The
motherboard and processor may take this speed, then again it may start up and
then shut down, it may even burn up the
processor!
So in closing I will say if you want to Overclock your processor and / or
memory do the research! Or you will be getting out your
wallet!
Note: After the Core 2 and Hyperthreading and the
advent of dual channel memory you can now mix memory FSB speeds. You can have a
set of memory modules that run at 400 MHz and another set of memory modules that
run at 800MHz by using dual channel memory and the over all memory FSB will
667MHz. Please note this will only work on the newer systems with dual cannel
memory.
If you are interested in learning more about Overclocking your processor, memory, or FSB I have written a six part e-course.
This site contains a lot of information. As
with any publication not all information is available due to space, time, or
subject constraints.
If you have a question that you did not find the answer
on this web site you a can
ask your question here and we will endeavor to get you the most up to date
answer possible!
