1. Basic Information
Overclocking an ATI SVGA card
- Introduction
High performance SVGA cards have become very popular now days. As you may be
aware, almost all PC components can be overclocked (CPU, Memory, CD-RW drive)
and of course SVGA cards. Our goal in this article, is to present an easy guide
for all users on how to get an additional performance boost, mostly when playing
their favorite game. We will describe how to overclock your ATI SVGA card, how
much performance you can possibly gain and how to test if your system is stable
enough. Let’s begin!
- Basic Overclocking Info
A SVGA card has two parts that can be overclocked. First, the GPU (Graphics
Processing Unit) and second the Video Board Memory. It is advised, in order
to find the maximum overclocking limits, not to have an overclocked CPU. The
basic idea is to increase the GPU clock speed, test, increase again, test until
you reach the limit.
But how do you know when you have reached the limit? Very simply, you will
start noticing the so-called “Artifacts”, which are graphic glitches
in your favorite game, or the system reboots. At that point you have reached
the GPU’s limit.
Lower the clock speed by 5 ~ 10 MHz and then repeat the process with the Video
Memory. Note, that usually the Video Memory won’t go as high as you would
wish, compared of course to the GPU. At this point, it is time to load up the
stability testing software and see if your graphics card can maintain 100% stability
for a long time. Running a stability test for something like six (6) hours will
ensure that you have a stable system with the maximum overclocking gain.
However, for most people the above procedure may sound rather complicated and
time consuming just to gain some FPS on their favorite game. Well, we have good
news for those of you who fall into this category. A new utility called “ATI
Tool” will make the above procedure so simple, that you only have to press
two buttons to find the maximum overclocking limits of your ATI card. The software
is still rather new, but from our tests it seem to work quite well…
2. Boost the GPU clock
Overclocking an ATI SVGA card - Page 2
- First Step
First of all, you will need an ATI SVGA card. In this guide we will be using
an ATI 9600Pro card. In order to overclock ATI cards, you need some extra software
that can raise the core and memory frequencies. While there is a range of software
for overclocking ATI cards (RivaTuner
, Rage3DTweak,
RadLinker/RadClocker,
and PowerStrip),
for this guide we will use the ATI
Tool v0.0.19. Download and install the software on your system. When you
run the application, you may see a dialog box similar to the following:

Hmm…Interesting! As the ATI Tool reports, the Radeon 9000/9200/9600 cards
are locked from overclocking by software drivers. This means that you may have
overclocked your card, but when starting a 3D application, the drivers will
return the card to its default values (GPU, Video Card Memory). For this reason
you must install “modified” drivers from http://softmod.ocfaq.com
that bypass this particular problem.
After pressing “OK”, the main application screen appears, displaying
the Core/Memory frequencies and several other options. By selecting the “Settings”
button, you can access the software menus, and further tweak the scanning engine:

As we mentioned earlier, the methodology “imposes” us to first
find the maximum Core limits and thereafter the maximum Video Memory frequencies.
The ATI Tool reports that our 9600Pro card works at 398.25/202.50 frequencies.
When pressing the “Find Max Core” button, an additional window will
appear, displaying a 3D cube. You will also notice that the Core/Memory slide
controls are disabled (grayed out) and in our case at least, the Core frequency
rose to 399.94.

After several seconds, the software locked the Core speed at 403.07 MHz and
started up the “Heat-Up Phase”, where it began to rotate the 3D
Cube in order to stretch the GPU/Memory to its limits while at the same time
looking for the so called “artifacts”. If the test passes without
any artifacts, the Core frequencies will rise, etc…

3. Changing the Memory Frequency - I
Overclocking an ATI SVGA card - Page 3
- First Step (Continue)
After 33mins, the software finally reported that the maximum Core frequency
is 480.21 MHz since no artifacts where detected for 600 seconds.

Note that you must tick the “Stop scanning for maximum clock” feature
at the software options to stop scanning after specific time; otherwise the
process continues for infinite time. Some people suggest leaving the whole process
running for no more than four (4) hours to test the SVGA stability.

Note that running the software several times can produce resulting figures
that might be different each time, with a very small variation. The following
picture shows the ATI Tool log file that gives further information about each
step

Having found the maximum Core frequency, we can now proceed to the Video card
memory. The ATI Tool again prompts us…

After pressing “OK” and “Find Max Mem” the same process
happens as we described before. When the software ends, it should have found
the maximum memory frequency, which in our case was 240.92 MHz.

4. Changing the Memory Frequency - II
Overclocking an ATI SVGA card - Page 4
- First Step (Continue)
After 33mins, the software finally reported that the maximum Core frequency
is 480.21 MHz since no artifacts where detected for 600 seconds.

ATITool will continue cycling through the tests indefinitrly unless you enable
the “Stop
scanning for maximum clock” feature
and set the maximum time to scan in the software options settings (see screenshot
below). It has been suggested that you need to leave the whole process
running for
no more than four (4)
hours in order to test SVGA stability.

Note that running the software several times can produce resulting figures
that might be different each time, with a very small variation. The following
screenshot shows the ATI Tool log file that gives further information
about each step

Having found the maximum Core frequency, we can now proceed to the Video card
memory. The ATI Tool again prompts us…

After pressing “OK” and “Find Max Mem” the same process
happens as we described before. When the software ends, it should have found
the maximum memory frequency, which in our case was 240.92 MHz.

5. FPS Benchmarks - Conclusion
Overclocking an ATI SVGA card - Page 5
- Test Results

As you will notice, the 3D Mark 2001SE score increased significantly when the
Core/Mem frequencies reached 480/240 respectively. At the default CPU speed
(2.4GHz) we had a gain of 1370 points, while with the CPU overclocked, there
was a gain of 1784 points.

At the 3D Mark2003 software test, we also saw a gain of 529 points when the
SVGA was overclocked and the CPU was run at default speed. The increase when
the CPU overclocked at 3.35GHz was lower (510 points). Due the way both 3D Mark2003
and 3D Mark2001 are designed, we won?t see much higher scores as the CPU increases
compared with the way GPU/Video Memory card increases.

Let?s now see a real life gaming test, using the UT2004 Demo. You will immediately
notice the big difference between the 73 and 94fps. Unlike with the 3D Benchmark
software, the CPU affects the performance here and that?s why we get a score
of 94fps when overclocking both CPU/SVGA card.
- Conclusion
The gaming industry plays a major role in the evolution of the PC, with gamers
enjoying their games when they play them at the highest possible speed. Considering
the wide range of SVGA cards on the market, the aim of this guide has been to
provide an easy way to gain a noticeable performance increase without spending
money. The latest generation of utilities like ATI Tool, do make SVGA overclocking
an easy task, also making users happy.
For hardcore gamers, there are several additional modifications
(BIOS updates) where even higher performance can be accomplished but the risks
are also higher. You might also consider water-cooling your SVGA card, which
provides more room for experimenting with higher Core/Mem frequencies than the
stock standard air ventilation solution. We plan to cover these two areas soon,
so stay tuned!