ATI
ATi Technologies produced graphics cards from the '80s through the mid '00s until merging with AMD in 2006. AMD still produces graphics cards today.
Contents
Graphics card series
Mach
Mach 8
Mach 32
Mach 64
Rage
3D Rage
3D Rage II
3D Rage Pro
Rage 128
Radeon
R100
The original Radeon was a Direct3D 7 visual processing unit (VPU), as ATi named it. It is a 2 pixel per clock design with 3 texture units on each of the pixel pipelines. The 166 MHz Radeon DDR (aka 7200) is competitive with GeForce 256 DDR. Clock speeds varied from 143 - 200 MHz, synchronous memory and core.
It supports environmental bump mapping (EMBM), unlike GeForce cards at the time. It has a basic form of anisotropic filtering that is high performance and offers a nice quality improvement but is highly angle-dependent and can not operate at the same time as trilinear filtering. It also offers ordered-grid supersampling anti-aliasing.
Backwards compatibility with old D3D 5 games is limited because of the lack of support for fog table and palettized textures. It is possible to enable fog table via registry tweaks but it was not officially supported.
RV100 (Radeon VE / 7000) is a chip with dual display capabilities but with reduced 3D hardware. It lacks T&L and has a single pixel pipeline. It is somewhat faster than TNT2 Ultra and G400 Max.
RV200 (Radeon 7500) is a die shrink of R100 with some improvements. It has more anisotropic filtering options and is capable of asynchronous clocking of memory and the core. The top of the line model is clocked at 290 MHz core and 230 MHz RAM, and competes with GeForce 2 Ti/Pro. There are many variations of this card.
Notes:
- DVI on these cards is flaky and is essentially unusable with DOS. High resolutions may also be problematic.
R200
This generation is the first with Direct3D 8 compliance, actually Direct3D 8.1. The Radeon 8500 is a 4 pipeline design with 2 texture units per pipeline and operates at up to 275 MHz, typically with synchronous core and RAM. It is competitive with GeForce 3 Ti 500.
Improvements over the R100 generation include the aforementioned Direct3D 8.1 support, meaning pixel shader 1.4 and vertex shader 1.1 support. A wide variety of supersampling anti-aliasing modes are available (2-6x, quality/performance) which use a programmable jittered grid. Anisotropic filtering is somewhat improved, with more levels supported, but is again very angle dependent and can not work with trilinear filtering. GeForce 3+ have higher quality anisotropic filtering but with a much higher performance impact.
Backwards compatibility with old D3D 5 games is limited because of the lack of support for fog table and palettized textures.
RV250 and RV280, known as Radeon 9000, 9200 and 9250, are slight evolutions of the design. They have somewhat reduced specifications but are more efficient and run cooler. They were popular notebook GPUs. Performance of Radeon 9000 Pro is not far off of Radeon 8500.
Radeon 9100 is a rename of Radeon 8500 LE.
Notes:
- DVI on these cards is flaky and is essentially unusable with DOS. High resolutions may also be problematic.
- With Star Wars KOTOR and KOTOR2, use Catalyst 4.2.
R300
The R300 GPUs are Direct3D 9 graphics chips. They have many improvements and noticeably better visual quality than prior chips. Radeon 9800 Pro is competitive with GeForce FX 5900 Ultra, but with Direct3D 9 games the GeForce FX falls far behind.
Anisotropic is vastly improved, with much lower angle-dependency and the ability to work with trilinear filtering. Anti-aliasing is now performed with 2-6x gamma-corrected rotated-grid multi-sampling anti-aliasing. MSAA operates only on polygon edges, which of course means no anti-aliasing within textures or of transparent textures, but expends far less fillrate and is thus useable at higher resolutions. NVIDIA does not match the quality of this MSAA until GeForce 8. However, ATi did not support any form of super-sampling with R300-R700, while NVIDIA did.
Backwards compatibility with old D3D 5 games is limited because of the lack of support for fog table and palettized textures.
Notes:
- With Star Wars KOTOR and KOTOR2, use Catalyst 4.2.
R420
This is ATi's Direct3D 9.0b generation. It is very similar to R300 in general, but with 16 pipelines in the top chip instead of 8, and higher clock speeds. They are still shader model 2.0 GPUs but have some extensions beyond 2.0, which gives them a 2.0b designation, but are not 3.0 compliant. This was not an issue until about 2 years after launch when games started to outright require shader model 3.0 or run without some visual features. There are some games that utilize 2.0b features - for example Oblivion has more visual effects available on X800 than 9800.
A new anti-aliasing mode was introduced, called temporal AA. This feature shifts the sampling pattern on a per-frame basis, if the card can maintain >= 60 fps. This works well with human vision and gives a tangible improvement to anti-aliasing quality. Also, while not initially available, adaptive anti-aliasing was added to the R420 series after the release of R520. Adaptive AA anti-aliases within transparent textures, giving MSAA more SSAA-like capabilities.
R520
A Direct3D 9.0c GPU with full shader model 3 features.
