ATI's Late Response to G70 - Radeon X1800, X1600 and X1300

Feature Overview

There are quite a few exciting new features being introduced with ATI's new X1000 series. Of course, we have a new line of hardware based on a more refined architecture. But at the end of the day, it's not the way that a company implements a dot product or manages memory latency that sells product; it's what consumers can do with the hardware that counts. ATI will not disappoint with the number of new features thtat they have included in their new top to bottom family of graphics hardware.

To provide a quick overview of the new lineup from ATI, here are the key featuers of the X1000 series.

• Fabbed on TSMC's 90nm process
• Shader Model 3.0 support
• Fulltime/fullspeed fp32 processing for floating point pixel formats
• New "Ring Bus" memory architecture with support for GDDR4
• Antialiasing supported on MRT and fp16 output
• High quality angle independent Anisotropic Filtering
• AVIVO and advanced decode/encode support

Shader Model 3.0 has been covered quite a bit over the past year and a half. To quickly summarize the differences, Shader Model 3.0 requires hardware to support dynamic flow control in both the vertex and fragment pipeline. This means that if/else statements and looping are possible. Rather than unrolling loops in programs, SM3.0 can keep instruction counts lower for complex operations. Also, conditional rendering allows unified shaders to run on large areas and do different things on different pixels. Other features such as two-sided lighting and vertex textures are also possible. The real advantages of SM3.0 come in the form of number of registers, branching, relaxed instruction limits, efficiency and accuracy (fp32 support is required). And all these features are now supported top to bottom on both NVIDIA and ATI hardware.

Running on a 90nm TSMC process has given ATI the ability to push clock speeds quite high. With die sizes small and transistor counts high, ATI is able to pack a lot of performance in their new architecture. As the feature list indicates, ATI hasn't just waited idly by. But the real measure of what will be enough to put ATI back on top will be how much performance customers get for their money. To start answering that question, we first need to look at the parts launching and their prices.

ATI X1000 Series Features
	Radeon X1300 Pro	Radeon X1600	Radeon X1800 XL	Radeon X1800 XT
Vertex Pipelines	2	5	8	8
Pixel Pipelines	4	12	16	16
Core Clock	600	590	500	625
Memory Size	256MB	256MB	256MB	512MB
Memory Data Rate	800MHz	1.38GHz	1GHz	1.5GHz
Texture Units	4	4	16	16
Render Backends	4	4	16	16
Z Compare Units	4	8	16	16
Maximum Threads	128	128	512	512
Avaialbility	This Week	11/30/2005	This Week	11/5/2005
MSRP	$149	$249	$449	$549

Along with all these features, CrossFire cards for the new X1000 series will be following in a few months. While we don't have anything to test, we can expect quite a few improvements from the next generation of ATI's multi-GPU solution. First and foremost, master cards will include a dual-link TMDS receiver to allow resolutions greater than 1600x1200 to run. This alone will make CrossFire on the X1000 series infinitely more useful than the current incarnation. We can also expect a better compositing engine built on a faster/larger FPGA. We look forward to checking out ATI's first viable multi-GPU solution as soon as it becomes available to us.

Rather than include AVIVO coverage in this article, we have published a separate article on ATI's X1000 series display hardware. The high points are a 10-bit gamma engine, H.264 accelerated decoding and hardware assisted transcoding. While we won't see transcoding support until the end of the year, we have H.264 decode support today. For more details, please check out our Avivo image quality comparison and technology overview.