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The Quick and the Totaled: ATI Radeon HD 2900 Pro Graphics Card Review (page 2)

Category: Video

by Alexey Stepin , Yaroslav Lyssenko

[ 11/26/2007 | 12:01 PM ]

Background of ATI Radeon HD 2900 Pro

Historically, ATI and Nvidia both released cheaper graphics cards based on cut-down versions of top-performance GPUs. You may remember the Radeon 9500 and 9500 Pro, GeForce 8600 GS, Radeon X800 GT and GTO, and Radeon X1800 GTO with Radeon X1900 GT. Although not optimal in terms of manufacturing cost, this approach is still better than the production of dual-chip solutions with two less advanced GPUs just because it doesn’t require developing a unique PCB. Moreover, it helps dispose of chips that didn’t pass the quality check and cannot work at the frequencies of the senior model or have defective subunits. The share of such chips may vary greatly depending on tech process, but they are always present in the total chip yield and can be used together with full-featured cores.

That’s the way the ATI Radeon HD 2900 Pro was born. Contrary to the expectations of many gamers and mass media, the configuration of the R600 chip the new card is based upon has not been cut down. The clock rates of the core and memory are the only parameters that suffered a reduction. Thus, the new Radeon has the following specs:

In other words, the ATI Radeon HD 2900 Pro is in fact an ordinary ATI Radeon HD 2900 XT with 512MB or 1GB of GDDR3 memory accessed across a 512-bit memory bus and a graphics core frequency of 600MHz. The reduction of the memory frequency is negligible. According to the manufacturer, ATI R600 chips are clocked at 24 different frequencies, but the difference between the frequencies of its subunits must be small as opposed to Nvidia’s chips. As a result, the reduction of the frequencies is going to have a serious effect on the performance of the Radeon HD 2900 Pro in games.

The ATI Radeon HD 2900 Pro in both its versions may be a very appealing product for users who prefer ATI’s solutions but it cannot become a real bestseller. Why? As far as we know, these graphics cards are indeed manufactured out of defective samples of the R600 that are not capable of working at 742MHz. The total amount of such cards is going to be about 10 thousand at best, which is just a drop in the ocean of consumer 3D graphics. Obviously, the introduction of the ATI Radeon HD 2900 Pro is a temporary measure AMD has resorted to in order to fill in the gap between the ATI Radeon HD 2900 and ATI Radeon HD 2600 families until the announcement and release of mainstream graphics cards based on the new RV670 core.