All modifications described henceforth
will void your warranty and if not done with proper care
can result in rendering the product non-functional.
Neither the author of this article nor TechSpot shall be
held responsible for any injury incurred or hardware
damaged when performing these modifications. Proceed at
your own risk!
Some Background
information
Quite contrary to our
previously published
GeForce4 volt-mod guide, Radeon boards found in the
market are not very similar, better put, there is a wider
component variance in the Radeon range of cards than in the
GeForce 4 range, therefore this guide will be less specific
than our first one; you might even be able to figure out how
to volt mod your Geforce FX with this guide if you do some
thinking on your own.
ATI has stayed true
to producing small cards; take for example the Radeon 9600
which is similarly sized as their top of the line Radeon
9800 Pro. But make no mistake, even if one could assume that
little differ between these, one would not be more wrong.
Because the Radeon 9600 runs at lower frequencies those
models are also equipped with power circuits that are not
able to deliver as much “oomph” as the 9800. However if you
look at the older, 9500 it does in fact use the same
high-end circuit as the 9700 (later revisions had a scaled
down power circuit though).
Things become even
more fun (and complex) when we start looking at the VPUs.
Radeon boards unlike GeForce4s do not share the same core.
The lower-end 9600 models come with a .13 micron core that
overclocks exceptionally well; the Radeon 9500 boards shares
the same .15-micron core as the 9700; Then the 9800 uses a
modified .15 micron 9700 core. Last but not least, there are
also memory setups of varying sizes that draw different
amounts of power and are rated for different nanosecond
operation that you will need to keep track of.
There now I hope you
are really confused, on top of that add customizations added
by ATI’s many third party vendors and you soon have no clue
what your card will be able to perform, this brings us to
the next step…
Trial and Error
The only way to know
how your particular card will overclock is by testing it, as
simple as that. Then, when you run into a limitation you
must first identify what is causing it and either fix it or
decide that this will be “fast enough” and quit playing
around before you end up with a dead card.
Overclocking
before modifying
The first thing you
must figure out is how far your card can be pushed before
any modding, download your favourite overclocking program
and give it a try. I use Powerstrip although you might
prefer something simpler if you are only going to overclock.
Our victim was an
Atlantis Radeon 9800 Pro board that we reviewed sometime
ago, Sapphire was kind enough of leaving the card for us to
play around. Right out of the box with no additional cooling
this card’s memory would overclock from 338 MHz (default) to
366 MHz.
At this point it is
quite reasonable to assume that the memory is running a bit
hot, so I bought some standard sized Alpha heatsinks and cut
them to fit and put on the memory modules. After I putting
them on with some Arctic Silver Thermal Adhesive and let it
set for the night my maximum memory overclock was up from
366 to 372 MHz. So now that I had reached the maximum memory
overclock without volt modding I put my attention towards
the core.
Since Radeon 9800s
use the same .15-micron core as the old trusty 9700 I was
not expecting to overclock it much, if at all. From the
standard clock speed of 378 MHz, I reached a core speed of
421 MHz, to say the least I put my old thoughts about poor
overclock-ability aside.
