Dave's Amiga Hardware Page
Overclocking since 1975!
After a hiatus of 10 years, I now have
the time to recommence mantaining and updating this site. There have
been a lot of changes during this time, and most pages in this site will
need to be updated in the coming months. This site is optimised for
Amigas using Ibrowse or Aweb with at least 1024x768 resolution. Pages on
this site may look untidy at lower resolutions. This website is proudly
compiled using the KISS principle!
Leaking clock batteries & capacitors - All Amiga users MUST read! Updated 27th may 2021.
What is overclocking?
Welcome to the Amiga Overclocking Website. Here you can learn how to
maximise your Amiga's performance at minimum cost. I have a very
extensive overclocking experience -I have been overclocking since 1975 -
when I first overclocked a calculator to make it faster than those
belonging to my schoolmates! Overclocking is a process where the
equipment being overclocked is made to run faster than it's design
speed. This is usually achieved by increasing the frequency of the
computer's clock. Often achieved by changing the oscillator module by
one rated at a higher frequency. It is a somewhat controversial
procedure - some like myself swear by it and overclock everything that
isn't bolted down! Others see it as totally evil - even worse than
Micro$oft - and claim that it will melt your computer and fry your cat!.
Perhaps some people have a problem with the concept of "getting
something for nothing" which is basically what overclocking is all
There are a number of practical considerations to bear in mind when
attempting an overclocking project. Firstly is the computer being
modified of "synchronous" or "asynchonous" design? Synchronous is where
the CPU is clocked at a speed which is a direct multiple of the main
clock which runs the entire computer. Examples of a synchronous computer
are standard A500, A1000, A1200 and A2000s. These machines are not easy
to overclock. The A3000 and the A4000 are of asynchonous design, having
a separate oscillator for the CPU and so are easier to overclock. If
you have an accelerator card in your Amiga, chances are that it is
asynchonous. I have also found over the years that the more recent mask
versions of a particular chip will often overclock to a higher
frequency. For example you would be more likely to get better results
from a new version 68060 compared to an older one. Likewise you will
usually get less from a chip at the top of it's range compared to a
lesser rated one. For example you will usually be able to overclock a
25MHz 68030 further (in percentage terms) compared to a 50MHz 68030.
The second consideration is heat generation. Due to increased
capacitive and inductive losses at the higher frequencies, the CPU (and
sometimes other associated chips) will run hotter. Care must be taken to
ensure they are cooled properly to avoid crashes or possible damage.
Cooling would have to be the most important part of overclocking.
Despite what critics say, I have NEVER had any damage caused by
overclocking, however it is best to be cautious, especially when an
expensive PPC chip is involved. Thirdly you need to bear in mind that
the accelerator card itself will also limit maximum possible
overclocking speeds. A good example is the Commodore A2630 which cannot
be clocked past 29MHz - even if you install a 50MHz 68030 in it.
Finally, bear in mind you will void any warranty applying to your
equipment. Of course, I will not be held responsible for any damage
caused by carrying out the modifications listed here. They are done at
your own risk. Listed below are several links to the different Amiga
CPUs I have overclocked, as well as other associated chips and hardware.
Click on them for more information. I currently have no information for
any hardware not listed here.
Other Amiga hardware sites.
Australian Amiga User Groups.
Other Amiga links.
Other links of interest.
- Overclockers Australia Australian PC overclocking site. Contains interesting tech news.
- Speedy A fascinating overclocking gadget for Macs, useable on Amigas - a variable clock oscillator!
- About me. Some personal information about myself and my 'Commodore Cave'. Last updated 27th May 2021.