Overclocking, for some, seems too good to be true, but it is very
possible (and sometimes fun) to do. However, overclocking can have its
consequences. When done improperly, damage may result in your system,
and in the worst case, a complete system failure. This guide will focus
completely on PCs, though it is possible to do on Macs as well. Also, if
you have absolutely no idea of the overclocking fundamentals, it is
suggested that you read this first
http://en.wikipedia.org/wiki/Overclocking
.
Steps
1. Know the precise definition of overclocking. "Overclocking is the
process of forcing a computer component to run at a higher clock rate
(the fundamental rate in cycles per second, measured in hertz, at which a
computer performs its most basic operations such as adding two numbers
or transferring a value from one processor register to another) than
designed or designated by the manufacturer".
2.Understand that not all computers can be overclocked. For one, laptops
are pretty much out of the question (some are overheating in stock
speed) . Also, any OEM (original equipment manufacturer) computer, such
as a Dell, HP or E-machine, will be more difficult to overclock, so your
best bet for overclocking is to purchase or build a custom system, but
keep in mind that some motherboards can't be used to overclock. Now
let's begin.
4.The BIOS. Overclocking is best done in the computer’s BIOS (Basic
Input/Output System or Binary Integrated Operating System). There are
also some motherboards that let you do a basic increase in power by
setting a jumper, but this is dangerous and you have no real stability
control. There are some software programs available which allow you to
overclock inside the operating system, but the best results are achieved
by changing BIOS settings. Usually you can get into your BIOS by
pressing DEL (some systems may use F2, F10, or Ctrl-Enter) as soon as
your computer begins the POST (Power On Self Test - when it shows the
RAM size, processor speed, etc.). Here, you can change your FSB (front
side bus), memory timings, and your CPU multiplier (also referred to as
CPU Clock Ratio).
5.Clearing your CMOS. Sometimes, an overclock can become unstable. If
this happens, or your computer will not boot, you will need to reset the
BIOS back to default and start over again. This is done by clearing the
CMOS (a small piece of memory on the motherboard which stores your BIOS
configuration, and is powered by a small battery). Some newer
motherboards will bypass user settings in the CMOS if the computer fails
POST (often caused by a faulty overclock). However, most motherboards
require a manual clear. This can be done in two ways, depending on your
motherboard. The first way is by changing the position of the clear CMOS
jumper on your motherboard, waiting a few minutes, then repositioning
the jumper to its original place. The second way, if your motherboard
doesn’t have this jumper, consists of unplugging your computer, removing
the little CMOS battery, then pressing the power button (your
capacitors will discharge), and waiting a couple of minutes. Then you
have to refit the battery and plug in your computer. Once your CMOS is
cleared, all BIOS settings are reset back to default and you’ll have to
start the overclocking process all over again. Just so you know, this
step is only necessary if your overclock becomes unstable.
6.Locked or Unlocked. The first thing to know when you start the process
of overclocking, is whether your processor is multiplier locked or
unlocked. To check whether your CPU is locked, lower your multiplier via
the BIOS one step, for example from 11 to 10.5. Save and exit your BIOS
and your computer will restart. If your computer posts again and shows
the new CPU speed, it means your CPU is unlocked. However, if your
computer failed to post (screen remains black) or no CPU speed change is
present, this means your multiplier is locked.
7.Multiplier Unlocked Processors. Usually, your max overclock is limited
by your memory, or RAM. A good starting place is to find the top memory
bus speed in which your memory can handle while keeping it in sync with
the FSB. To check this, lower your CPU multiplier some steps (from 11
to 9, for example) and increase your FSB a few notches (e.g.: 200 MHz to
205 MHz). After this, save and exit your BIOS. There are a few ways to
test for stability. If you make it into Windows, that is a good start.
You can try running a few CPU / RAM intensive programs to stress these
components. Some good examples are SiSoft Sandra, Prime95, Orthos,
3DMark 2006 and Folding@Home. You may also choose to run a program
outside of Windows, such as Memtest. Load a copy of Memtest onto a
bootable floppy, then insert the disk after you have exited the BIOS.
Continue to increase your FSB until Memtest starts reporting errors.
When this happens, you can try to increase the voltage supplied to your
memory. Do note that increasing voltages may shorten the life span of
your memory. Also, another option is to loosen the timings on the memory
(more on this a bit later). The previous FSB setting before the error
will be your max FSB. Your max FSB will fully depend on what memory you
have installed. Quality, name-brand memory will work best for
overclocking. Now that you know your max FSB, you’ll figure out your max
multiplier. Keeping your FSB @ stock, you raise your multiplier one
step at a time. Each time you restart, check for system stability. As
mentioned above, one good way to do this is by running Prime95. If it
doesn’t post (reread the section about clearing the CMOS), or Prime 95
fails, you can try to raise the core voltage a bit. Increasing it may or
may not increase stability. On the other hand, the temperature will
also be increased. If you are going to increase the core voltage, you
should keep an eye on temperatures, at least for a few minutes. Also
note that increasing voltages may shorten the life span of your CPU, not
to mention void your warranty. When your computer is no longer stable
at a given multiplier setting, lower your multiplier one step and take
that as your max multiplier. Now that you have your max FSB speed and
your max multiplier, you can play around and determine the best settings
for your system. Do note that having a higher FSB overclock as opposed
to a higher multiplier will have a greater impact on overall system
performance.
8.Multiplier Locked Processors. Having a multiplier locked processor
means that you can only overclock by increasing the Front Side Bus.
We’ll just follow the same strategy as applied in the beginning of the
unlocked processors step. Basically, raise the FSB in small increments,
and after each post, check the system for stability (Prime95 or
Memtest). Also remember that increasing your CPU or RAM voltage can give
you more stability. When you reach your peak FSB (probably because of
your memory), you can try to get a little further by relaxing your
memory timings.
9.Getting Your System Stable. Now that you have an initial overclock,
whether with a locked or unlocked processor, you have to tweak the
system to get it absolutely stable. This means you have to change the
variables (Multiplier, FSB, voltages, memory timings) until the system
is rock solid. This is mainly a trial and error process and takes up
most of the time when overclocking a system. Here are some thoughts:
Your system will start acting strange if your motherboard doesn’t have a
PCI /AGP lock. Having a PCI/AGP lock will keep the frequency of your
PCI and AGP bus at 33 and 66 MHz respectfully, even if you raise your
FSB. Without this lock, the PCI and AGP bus speeds are increased with
the FSB, eventually reaching a point where they no longer function
correctly. Some motherboards have this lock and some don’t. Check your
motherboard / BIOS for such an option. Remember that increasing your
voltage will almost always make your system more stable. But as stated
before, your temperature will sky rocket and the components lifetime may
be decreased. Therefore, the goal is to find the lowest voltage
settings at which your system is stable. Decreasing your FSB a few
notches may also provide a stable overclock. Sure, you may not want to
lower your max overclock, but lowering your FSB 1-2 MHz can mean the
difference between a stable system and a BSOD after 25 minutes of
gaming. Sometimes, a very high temperature can cause instability as
well, so be sure to keep your processor at a decent temperature. One of
the ultimate stress tests is Prime 95. When you think your system is
stable, run the blend torture test for 12 hours and see if you get any
errors. If you don’t, then you should be set. If errors are present, go
back to the drawing board. Lower your FSB, increase your voltage, relax
your memory timings, etc.
10.Test Utilities. These utilities are designed to put your memory
through its paces. If you've got a faulty module or an unstable
overclock, these programs will find it. Either one can be loaded onto a
floppy disk and used to boot the computer from. They can also be a real
life-saver when testing the limits of your hardware. Spare yourself the
chance of corrupting a hard drive file system, figure out what works
with these first. To use, simply put the program on a floppy disk and
boot the computer. The utility will automatically load and begin running
the tests. You may find that a CPU overclock that runs either Memtest
or WMD successfully without error may not be completely stable in
Windows. In these cases, typically a slight increase in CPU voltage will
usually resolve the problem. CPU-Z is probably the most popular program
to verify and display your system overclock. With the latest version
there's even a way to submit your overclock online for verification and
to get a comparison link, similar to many graphics benchmarking
programs. WCPUID is a similar program, however it has not been updated
in some time, and may not recognize all the latest processors and
chipsets. Also below are a few Windows-based programs that can help you
verify you've got a stable overclock before you actually start using
your computer for other tasks. In step 6 it was mentioned that
Folding@Home can be used to test stability, however a failure often
results in losing the work unit, which is why most people don't like to
use F@H for this purpose.
11.Memory Timings. Memory timings or latency refers to how quickly the
system can get data in and out of the RAM. This is different from Memory
speed, or the frequency that the memory runs at in relation to the
processor and system bus. Think of it in terms of a mass-transit system.
The memory speed is the rate at which the Metro train moves from
station to station. The latency measures how quickly the people can move
on and off the train at each stop. Generally, the lower the memory
timing value, the less latency there is, and the faster the memory
responds. Most BIOS are configured by default to Auto detect timings
from the memory module by SPD or Serial Presence Detect, however many
have the option to change this to manual so that the user can adjust the
settings individually. SPD values are programmed into the memory by the
manufacturer, and are typically printed on a label on the side of the
module. Timings are usually referred to in this order, along with some
available settings in the BIOS. CAS is sometimes referred to as CL or
Cycle Length. Some motherboards have an option as low as 1.5 for this
setting. But the effect of CAS on memory latency is much less than tRCD,
tRP or CMD. CMD or Command Rate has the most effect on memory
performance. Not all memory and/or motherboards are capable of running a
1T CMD however. SPD
Values
Memory manufacturers and overclockers usually refer to memory timings in
the same order as listed above. For example, some low-latency memory
might indicate CL2 2-2-5 right on a sticker on the module itself. Some
memory (such as TCCD) may be rated differently at different speeds such
as low timings of 2-2-2-5 at PC3200 (200 Mhz DDR400) and higher timings
of 3-4-4-8 at PC4400 (275 Mhz DDR550). Many memory modules do not
advertise CMD so you should check reviews before purchasing to get an
idea if it will run at 1T.
12.Memory chip quality. There are many manufacturers of individual
memory chips (such as Samsung, Winbond, Hynix) and also manufacturers of
memory modules (such as Corsair, Kingston, OCZ) who use other
companies' chips to make their modules. Memory chips are tested and
"binned" by the manufacturer following production and then sold to other
companies to make the modules. Some chip manufacturers (such as
Samsung, Geil) also make their own modules. Memory chips come in many
different flavors so there are a few things to watch for. BH5, or more
specifically, Winbond BH-5 chips, have become almost legendary in the
overclocking enthusiast world for their ability to run at low latency
timings, even at high speeds, albeit when supplied with an extreme
amount of voltage. More recently, companies have taken to using
BH5-based UTT chips to satisfy overclockers' needs. Some people have had
good luck with modules made using these chips, however be aware that
the UTT designation means that the chips came untested from the
manufacturer. When memory manufacturers have a wafer come off the line
that for whatever reason doesn't meet specification, rather than scrap
the entire piece they often (depending on market demand) sell off the
chips as UTT and it's up to the module manufacturer then to test the
chips and determine if they're any good. Since these come out of at
least a partially defective wafer, it can't be said with any certainty
that the chips can take all the extra voltage and speeds people throw at
them. In any case, both UTT and BH5 based modules are typically only
good up to ~225 Mhz at the voltages available on most motherboards,
i.e.. 2.85 to 2.9 volts. Many DFI motherboards are capable of supplying
more than 3 volts to the memory, up to and even including 4 volts! If
you don't have a DFI board, you can check out OCZ's DDR Booster to see
if it's compatible with your motherboard. For many boards the Booster
will give you from 3.4 to 3.8 volts available. The Samsung TCCD is
another type of chip that has caught on lately, and may just surpass the
BH-5 for "King of the Memory Hill" because it can run at tight timings
at default speeds, loose timings at much higher frequencies, and doesn't
require much more than stock voltage to keep it running. Most system
memory made today is of the TSOP variety, or Thin Small Outline
Packages, rather than BGA (more commonly found on video cards) or Ball
Grid Array. The names have to do with the way the chips are made and how
they attach to the circuit board of the memory module.
13.Athlon 64 Overclocking. Although previous steps of this guide was not
processor-specific, the procedures detailed above apply more to Socket A
overclocking than the latest A64 chips. There are some significant
differences which are worth mentioning to help you get the most out of
your Socket 754 or 939 processor. First off, the A64 does not really
have a FSB or front side bus speed per se. The term FSB refers to the
frequency of the connection between the CPU and Memory Controller. On an
Athlon XP chip this could be 133, 166 or 200 (effective 266, 333 or 400
DDR) depending on the model. But the Memory Controller is integrated
into the processor on an A64 chip and therefore runs at the same speed
as the CPU. There is a connection to the Northbridge on the motherboard
however, called the Hypertransport Link, which can be either 800 Mhz
(effective 1600) on Socket 754 or 1000 Mhz (effective 2000) on Socket
939. Now the Hypertransport Link speed is determined from the base HTT
speed of 200 (referred to as CPU Frequency in this BIOS above) times the
HT Multiplier (shown as HT Frequency below) which is by default, 4x on
S754 and 5x on S939. It is very important to remember to lower the HT
Multi as you increase HTT. Ideally you want to try to keep the overall
link speed close to the default 800 or 1000 as going much above these
will result in instability. There are cases where someone complains they
can't get more than 220-230 HTT on their overclock and think they've
topped out the memory or CPU. Had they reduced the HT Multiplier by one
step more they likely would have found they could keep going higher on
the HTT. Anyway, back to this. The principle behind the CPU Multiplier
is the same for A64, only now they refer to it as the FID, or Frequency
ID. If you take the base HTT frequency and multiply it by the FID you
end up with the speed that the CPU runs at. Unfortunately with A64
processors, only the default multi and lower is unlocked and available
to use. Some BIOS will allow half-steps on the FID, however these have
been shown to either cause instability or not even work at all, so it's
best to just stick with the full multi's. FX chips have all multipliers
unlocked, so these can be adjusted both higher or lower than the factory
default. Unlike AXP systems, with A64 it is not as important to make
sure the FSB remains synchronous with the memory speed. While benchmarks
will show a slight increase staying with a 1:1 ratio, going
asynchronous is not the detriment to performance it once was.
Considering the high speeds available to modern S754 and S939 processors
and motherboards, it's a good thing that memory dividers can be
implemented. Speaking of memory dividers, this is another setting that
sometimes confuses people. While the idea of memory ratios or dividers
have existed for a while, AMD users were always told not to use them.
Now that we can use them we need to understand that the exact ratio
changes slightly depending on the CPU multiplier you use. The reason for
this is with the memory controller built into the processor, any
divider used takes into account the CPU Multiplier when calculating the
ratio. See the chart that shows what the different settings for memory
divider in BIOS will result in. The numbers in the top row correspond to
the memory speed setting in the BIOS. Some motherboards will only have
standard JDEC speeds available such as 200, 166, 133 and 100 whereas
others may have the listed "in-between" speeds. The number in
parenthesis beside the memory speed indicates the hypothetical ratio for
that particular setting. For example, to run memory at 166 we start by
taking the base frequency of 200 and multiply that by the ratio of 5/6
and we get 166.66 exactly. However, as mentioned above, the ratio has to
be a factor of the CPU Multiplier, so we need to look at the row
indicated by the multiplier being used. For example, a 3000+ "Venice"
stock multi is 9x, so if you come down to that row, then move across the
row to the 166 memory column you find that the ratio used for this
setting will actually be 9/11 rather than the 5/6 as indicated at the
top. The 9/11 ratio yields a memory speed of 163.63 which is close, but
not quite the same as what it should be for a true 166 speed. This is
not a problem but just something to be aware of.The Different Settings for Memory Divider in BIOS
for looking video tutorial
http://www.youtube.com/watch?v=bpwcQH-AATE&feature=player_embedded
Monday, August 6, 2012
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wah oveclocking pc memang bagus sih tapi agak susah untuk yang belum terbiasa
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