iXBT Labs - Computer Hardware in Detail






ATI RADEON 9800 XT: Extreme Overclocking



  1. Introduction
  2. Testbed, test tools
  3. Test results: extreme overclocking at -15°C
  4. Conclusion

As always, winter brings real frost and snow, and we got a good chance test our cards in frosty conditions...

...You ask why does the collage reflect summer? Well, first of all, winter is not everywhere - the southern hemisphere got summer and the peak of heat right now:-). Secondly, we are speaking about overclocking today, and the picture shows that the card is able to jump far ahead.

So, we are overclocking today one of the most powerful cards. The GeForce FX 5900 Ultra already went through such test, the GeForce FX 5950 Ultra wouldn't differ much from it, that is why it doesn't make sense to come back to the whole family. At the same time, the RADEON 9800 XT hasn't been yet in its shoes.

But before we start overclocking the card have a look at the list of reviews devoted to the RADEON 9800.

Theoretical materials and reviews of video cards which concern functional properties of the GPU ATI RADEON 9500/9700/9800 

Traditionally we carry out the winter overclocking tests on the balcony at the air temperature below 0. It has both strong and weak points relative to overclocking in a freezer. The plus is that you don't have to prepare your freezer and arrange all the components inside so that the cables can reach them and the display. The minus is that you have to arrange all the stuff near the balcony door so that there was a place for the display and tester as well. Also, the tester can easily catch cold :)

So, one winter morning when the thermometer showed -12 C I tool out all the stuff on the balcony that was covered with snow. Although it was frosty, the coolers didn't stop and the hard drive struggled to remain alive. The video card reached excellent scores (see below).

At the end I touched the card and cooler on the processor to make sure they were warm  - well, I contributed my mite into the global warming...)

First, I wanted to run 2-3 test games but then I realized that I could endure only one of them. That was Unreal II as it reflects the most realistic correlation of video cards' power for today.


The Hercules 3D Prophet 9800 XT card tested today was already examined before, and I'll just briefly remind you its specs: 

Hercules 3D Prophet 9800 XT 256MB

Hercules 3D Prophet 9800 XT 256MB
AGP x8/x4 interface, 256 MB DDR SDRAM memory in 8 chips on both PCB sides. 

Hynix (HY5DU573222) 2.5ns memory chips (corresponds to 400 (800) MHz), memory clocked at 365 (730) MHz, GPU at 412 MHz. 256 bit memory bus.

Comparison with the reference design, front view
Hercules 3D Prophet 9800 XT 256MB Reference card ATI RADEON 9800 XT

Comparison with the reference design, back view
Hercules 3D Prophet 9800 XT 256MB Reference card ATI RADEON 9800 XT


This is actually a copy of the reference card. 

Testbed and drivers


  • Pentium 4 3200 MHz based computer:
    • Intel Pentium 4 3200 MHz CPU;
    • DFI LANParty Pro875 (i875P) mainboard; 
    • 1024 MB DDR SDRAM; 
    • Seagate Barracuda IV 40GB HDD; 
    • Windows XP SP1; DirectX 9.0b;
    • ViewSonic P810 (21") and ViewSonic P817 (21") monitors.
    • ATI 6.404 (CATALYST 3.10) driver.

VSync off, S3TC off in applications, OverDrive off. 

Test results: Extreme Overclocking

Test application:

The today's tests are not traditional, it's the analysis of video card's performance gain with independent overclocking of the core and memory at the ambient temperature -12°C. 

At such temperature the card worked steadily at 600/860 MHz (it also operated at 610 MHz but not without artifacts). 

Unreal II: The Awakening


Without AA and and anisotropy


Memory clock fixed, core clock changes


Core clock fixed, memory clock changes


Combined overclocking


AA and anisotropy enabled


Memory clock fixed, core clock changes


Core clock fixed, memory clock changes


Combined overclocking



  1. At 1024x768 the performance is limited by the CPU clock (and by the system as a whole), the gain was inconsiderable with AA and anisotropy disabled.
  2. Overclocking in the heavy modes yields the 30% gain. The main bottleneck is the memory which couldn't reach so great scores like the core. The modes with AA and anisotropy enabled prove it: performance reacts mainly to the memory clock growth, and it grows faster as the core clock goes up at the high memory frequencies rather than at the low ones.
  3. If the next product has the same architecture and the clock speeds around 600/1000 MHz, the performance of such card can be higher by approximately 40% relative to the current flagship (in heavy modes).

The tests were carried out just for love, and we do not urge you to take your PC stuff out to the balcony :).

In our 3Digest you can find full comparison characteristics for video cards of this and other classes. 

Andrey Vorobiev (anvakams@ixbt.com)

Write a comment below. No registration needed!

Article navigation:

blog comments powered by Disqus

  Most Popular Reviews More    RSS  

AMD Phenom II X4 955, Phenom II X4 960T, Phenom II X6 1075T, and Intel Pentium G2120, Core i3-3220, Core i5-3330 Processors

Comparing old, cheap solutions from AMD with new, budget offerings from Intel.
February 1, 2013 · Processor Roundups

Inno3D GeForce GTX 670 iChill, Inno3D GeForce GTX 660 Ti Graphics Cards

A couple of mid-range adapters with original cooling systems.
January 30, 2013 · Video cards: NVIDIA GPUs

Creative Sound Blaster X-Fi Surround 5.1

An external X-Fi solution in tests.
September 9, 2008 · Sound Cards

AMD FX-8350 Processor

The first worthwhile Piledriver CPU.
September 11, 2012 · Processors: AMD

Consumed Power, Energy Consumption: Ivy Bridge vs. Sandy Bridge

Trying out the new method.
September 18, 2012 · Processors: Intel
  Latest Reviews More    RSS  

i3DSpeed, September 2013

Retested all graphics cards with the new drivers.
Oct 18, 2013 · 3Digests

i3DSpeed, August 2013

Added new benchmarks: BioShock Infinite and Metro: Last Light.
Sep 06, 2013 · 3Digests

i3DSpeed, July 2013

Added the test results of NVIDIA GeForce GTX 760 and AMD Radeon HD 7730.
Aug 05, 2013 · 3Digests

Gainward GeForce GTX 650 Ti BOOST 2GB Golden Sample Graphics Card

An excellent hybrid of GeForce GTX 650 Ti and GeForce GTX 660.
Jun 24, 2013 · Video cards: NVIDIA GPUs

i3DSpeed, May 2013

Added the test results of NVIDIA GeForce GTX 770/780.
Jun 03, 2013 · 3Digests
  Latest News More    RSS  

Platform  ·  Video  ·  Multimedia  ·  Mobile  ·  Other  ||  About us & Privacy policy  ·  Twitter  ·  Facebook

Copyright © Byrds Research & Publishing, Ltd., 1997–2011. All rights reserved.