Specifications

While ATI has introduced a new high-end product roughly every 6-9 months pretty routinely for the past few years, as you probably know, each of these new graphics cores has been fundamentally a follow-up part to ATI’s RADEON 9700 graphics card first introduced in the summer of 2002. The RADEON 9800 and 9800 XT families were both more of the same, only with higher clocks, while the X800 series added 2.0b shaders, more pipelines, a new manufacturing process with higher clock speeds, and other goodies such as temporal AA and 3Dc.

Sure, each of these follow-up cards delivered substantially more performance than ATI’s original RADEON 9700 PRO, but ATI didn’t exactly reinvent the wheel in the process. Ultimately this was beginning to catch up with them as an increasing number of shader model 3.0 titles have shipped in the past six months (fortunately for ATI they were largely able to get around this dilemma with clever patches for the most prominent titles that added 2.0b shader support).

With RADEON X1800, all that has changed, as the R520 VPU it’s based on has been built from the ground up on an entirely new architecture. Let’s take a look at the specs:

90 Nanometer Technology

Faster clock speeds

Double the transistor density of earlier 130nm technology

320 million transistors

New Performance Architecture

High efficiency Ultra-Threaded Pixel Shader Engine

Supports Shader Model 3.0 at speeds several times faster than any existing
technology

16 pixel pipelines

8 vertex pipelines

625MHz graphics core with 256MB or 512MB of GDDR3 memory at 1.5GHz on RADEON X1800 XT

New Memory Controller Design

Supports the fastest available memory speeds

512-bit internal ring bus

New cache design, improved HyperZ, latency improvements

Next-Generation Image Quality

Advanced High Dynamic Range rendering with anti-aliasing supported, 128-bit floating point precision

New adaptive anti-aliasing mode combines image quality of supersampling with speed of multisampling

New high quality anisotropic filtering mode

Avivo™

Revolutionary display, video, and connectivity capabilities

Consumer electronics convergence features

CrossFire™

Powerful parallel graphics processing support

Notes

Arguably the most notable items that stood out from the specifications list above are the X1800 XT’s high clock speeds (600MHz+, roughly 200MHz faster than GeForce 7800 GTX) and the number of pipelines. After rumors speculating that R520 boasted 24 or even 32 pixel pipelines, we now see that the chip sports the same number of pipelines as its predecessor (with one texture unit per pixel pipeline), although with approximately 320 million transistors inside (twice that of the RADEON X800 from a year ago), ATI obviously incorporated quite a few new features into R520. ATI is quick to point out that RADEON X1800 supports HDR with multisample AA; a feature which NVIDIA currently doesn’t provide with any of their GPUs. Apple Cinema display users will also be happy to know that the RADEON X1800 XT supports dual-link DVI.

Of course, with a new architecture comes new nomenclature to read up on. With that in mind, lets quickly go over a few of the most notable changes ATI has integrated into the RADEON X1800.