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High Definition Gaming or Features and Peculiarities of RADEON X800 XT/PRO
Having announced new X800 (R420) architecture and a new RADEON X800 XT and RADEON X800 PRO graphics processor family, ATI also introduced a new concept of High Definition Gaming.
The concept of High Definition Gaming appeared due to wide spreading of HDTV – high definition television - and HDTV supporting display devices.
The image quality in HDTV standard can hardly be compared with ordinary image quality, as it is not just a much higher resolution or higher level of detail, but a completely new level of image quality at all. ATI compares the appearance of HDTV with the transition from black-and-white to color images: most people who have once seen HDTV image quality, will have hard times shifting back to regular stuff.
ATI compares the impressions made by HD Gaming on personal computers with those made by the shift to HDTV video quality: it includes stably high fps rate in the highest resolutions, including 1600x1200 and 1920x1080, incredible level of detail, new level of image quality, realistic effects and really living worlds.
X800 architecture capable of implementing HD Gaming includes a number of absolutely new technologies, as well as a number of technologies inherited from the previous architecture and improved accordingly. The marketing names for the technologies remained the same, but instead of the numeric indexes we now have HD suffix:
SMARTSHADER HD: vertex and pixel X800 processors;
SMOOTHVISION HD: anisotropic filtering and full0screen anti-aliasing algorithms;
HYPER Z HD: technologies improving the efficiency of the available memory bus bandwidth;
3Dc: new compression method for normal maps.
Before we pass over to the details hiding behind these marketing names, we would like to offer you a comparative table with the features of the most high-performance graphics processors of the previous and current generations: ATI RADEON X800 XT Platinum Edition, ATI RADEON 9800 XT, NVIDIA GeForce 6800 Ultra and NVIDIA GeForce FX 5950 Ultra.
ATI RADEON X800 XT Platinum Edition | ATI RADEON 9800 XT | NVIDIA GeForce 6800 Ultra | NVIDIA GeForce FX 5950 Ultra | |
Manufacturing technology | 0.13micron low-k | 0.15micron | 0.13 micron | 0.13micron |
Number of transistors | 160 mln. | 110 mln | 220 mln | 125 mln |
Clock frequency | 520MHz | 412MHz | 400MHz | 475MHz |
Graphics memory controller | 256bit DDR/DDR2/GDDR3 SDRAM | 256bit DDR/DDR2 SDRAM | 256bit DDR/DDR2/GDDR3 SDRAM | 256bit DDR SDRAM |
Graphics memory clock frequency | 1120 (560 DDR) MHz | 730 (365 DDR) MHz | 1100 MHz | 950 (475 DDR) MHz |
Memory bus peak bandwidth | 33.4GB/s | 21.8GB/s | 32.8GB/s | 28.3GB/s |
Maximum graphics memory size | 512MB | 256MB | 512MB | 256MB |
Interface | AGP 3.0 4x/8x | AGP 3.0 4x/8x | AGP 3.0 4x/8x | AGP 3.0 4x/8x |
Pixel processors, pixel shaders | ||||
Shader model | 2.x | 2.0 | 3.0 | 2.x |
Static loops and branching | yes | no | yes | no |
Dynamic loops and branching | no | no | yes | no |
Multiple Render Targets | yes | yes | yes | no |
Floating-Point Render Target | yes | yes | yes | no |
Maximum number of pixels per clock cycle | 16 | 8 | 16 | 4 |
Maximum number of Z values per clock cycle | 16 | 8 | 32 | 8 |
Number of texturing samples | 16 | 8 | 16 | 8 |
Texture filtering algorithms | Bi-linear, | Bi-linear, | Bi-linear, | Bi-linear, |
Maximum level of anisotropy | 16õ | 16x | 16x | 8x |
Vertex processors, vertex shaders | ||||
Shader model | 2.õ | 2.0 | 3.0 | 2.x |
Number of vertex processors | 6 | 4 | 6 | 3 |
Static loops and branching | yes | yes | yes | yes |
Dynamic loops and branching | no | no | yes | yes |
Reading textures from the vertex shader | no | no | yes | no |
Tesselation | no | no | no | no |
Full-Screen Anti-Aliasing | ||||
FSAA algorithms | Rotated-grid multi-sampling, | Rotated-grid multi-sampling | Ordered-grid super-sampling, | Super-sampling, |
Number of samples | 2,4,6 | 2,4,6 | 2..8 | 2..8 |
Technologies increasing the efficiency of the memory bus bandwidth | ||||
Hidden Surface Removal (HSR) | yes | yes | yes | yes |
Texture, Z-buffer, frame buffer compression | yes | yes | yes | yes |
Fast Z-buffer clear | yes | yes | yes | yes |
The specifications listed in this table let us make one conclusion: due to higher clock frequency, RADEON X800 XT Platinum Edition shouldn’t yield in performance to NVIDIA GeForce 6800 Ultra, and the functional differences should really be minimal, even though ATI doesn’t claim the support of shader version 3.0. They only state that their solution supports shader version 2.x, however, the functional level of the new RADEON X800 series is closer to shader version 3.0 than to the good old shaders of the R300 generation.
But, let’s not rush ahead of time and discuss everything from the very beginning.
