Summary: Tyan is an established player in the motherboard market, but like many motherboard manufacturers they're now producing video cards as well. The Tachyon G9000 Pro is their first foray into this field and as its name suggests, it's based on ATI's RADEON 9000 PRO core. See how this card performs in today's review!
With ATI having taken a significant technology lead with their R300 core, leaving themselves exclusively to the high-end market was certainly not a part of their agenda. With lower margins and higher volume, the low-end and mid-range markets are prime territory for anyone, and certainly not segments that ATI intended to neglect. Developing a scaled back version of the R200ís core, RV250 was created. From that, ATI introduced RADEON 9000 PRO, a high performance, low-cost derivative of last yearís RADEON 8500.
Being aware of the detriment brought about by relying on one's boards sales exclusively, ATI has allowed other board manufactures to distribute products based on their architectures. Tyan, being one such board manufacturer, has produced their Tachyon 9000 Pro. Based entirely off of ATI's RADEON 9000 PRO reference design, both RADEON and Tachyon include 64 MB of 275 MHz DDR memory (though R250 supports up to 128MB of memory), with core clocks operating at 275 MHz.
Letting ones chip into the open market for a variety of board manufactures to produce, while primarily advantageous, can also be a detriment. While all based on the same chip that one produces, higher margins are gained through direct board sales. Competition is also created, which can drive down prices without some type of price regulation on the chip manufacturerís part. In the case of ATI's partnership with Tyan, Tachyon sales allow for further market penetration, while potentially reducing ATI's own board sales.
The feature set of RV250 is primarily based on that of R200. Running at a 275 MHz core clock allows for RV250 to provide a theoretical fill-rate of just over 1 Gigapixel/sec while supporting pixel shader version 1.4. Unlike R200 though, RV250 includes only a single texture unit, requiring all multi-texture rendering to be multi-cycle. This, however, does not require multi-pass rendering, as 6 textures can be written in a single pass via loopbacks, or reuse of texture coordinates. From this we can ascertain that applications that require multi-texturing will operate more efficiently on R200-based products.
ATI's SMOOTHVISION technology is used in RV250 as well. It is in many ways similar to the anti-aliasing implementation found on Voodoo5, with some slight variations. Where Voodoo5 used a fixed jittered sampling position, SMOOTHVISION uses variable sampling, based on a select set of sampling patterns.
ATI's implementation of anisotropic filtering has certainly been a topic noteworthy of discussion. Anisotropic filtering is unique in that it filters in a non-uniform pattern, increasing overall quality and image accuracy. ATI's implementation is strictly bilinear in that it only filters within a single mip-map level. Other implementations, such as NVIDIA's, provide greater quality by using a trilinear anisotropic filter, filtering across mip levels.
HyperZ-II is found onboard Tachyon as well, as with all RV250 based boards. Besides a variable rate lossless Z-Buffer compression, a hierarchical Z-buffer is the primary feature of this. ATI's implementation of this uses 8x8 pixel blocks for hierarchical Z-buffering. The nearest vertex value from the 8x8 block is taken and compared to a stored reference value. This comparison tests to see whether any of the pixels within the block are visible. If the nearest pixel in the block is deeper than the reference value, the pixel block is discarded. If the vertex is nearer than the reference value, the block is rendered.
The Tachyon G9000 card
Tyanís Tachyon G9000 Pro closely follows ATIís RADEON 9000 PRO reference design. Components are placed identically, which isnít surprising considering that the dual 400MHz DACs, TV encoder, and other video circuitry are now integrated on the RADEON 9000 core itself. As a result there isnít much card manufacturers such as Tyan can do to make their products stand out from each other.
With the Tachyon 9000 Pro sharing the same reference design as ATI's incarnation, both boards share the same connections. Included are the standard SVGA connection, as well as DVI and video out. Through the SVGA and DVI connection, dual displays can be connected through what ATI terms their HYDRAVISION software. Additionally, video output is included with an adapter allowing for both composite and S-video out.
Overclocking the Tachyon proved fairly painless. Loading up a third party overclocking utility such as Powerstrip, it was not an issue to pull a few more frames per-second out of the board. When overclocking the core, Tachyon did find itself with a potential advantage in that it provided an overall better active cooling system than Radeon 9000 Pro. The heatsink onboard Tachyon was roughly double the size of ATIís RADEON 9000 PRO card, providing more efficient heat removal.
AMD Athlon XP 1900+
Shuttle Spacewalker AK32A KT266A motherboard
512 MB DDR SDRAM
ATI Radeon 9000 Pro 64 MB
Tyan Tachyon 9000 Pro 64 MB
Catalyst 2.3 Drivers: v220.127.116.1166
Hercules Muse 5.1 DVD
Windows XP Professional
Desktop Resolution 1024x768x32 at 75 Hz
All benchmarks done at 32-bit color
3D Mark 2001 SE
3DMark gives us an overall picture of the Tachyon's performance. Fill-rate was found to be slightly lower overall on Tachyon, which for the most part was consistent with other benchmarks. As seen by the recorded number, Tachyon and Radeon both come up more than 400 MPPS short of their theoretical peak. This shortage can be attributed to a variety of factors, yet specifically memory bandwidth.
The 3DMark lobby scene is certainly indicating a CPU and T&L limitation. Fill-rate remains available to spare for resolutions up to 1024x768. From this point we see a noted fall off, indicating that a fill limitation is taking place.
Serious Sam 2
Serious Sam 2 showed consistent playability, even at 1600x1200. Granted, at this resolution, some level of slow down exists, 1280x1024 showed definite playability levels. What we also note is that Tachyon showed a slightly reduced level of performance throughout all resolutions when compared to Radeon.
Quake III Arena
Performance levels in Quake III were pretty much expected. Up to 1024x768, there are definite CPU limitations. From there, fill-rate becomes a factor and performance degrades. The variations between Tachyon and Radeon are clearly minor, with Tachyon taking the lower resolutions and Radeon taking the upper of those.
Quake 3 Ė 2x AA
Quake 3 Ė 4x AA
Anti-aliasing performance was pretty low, as is typical with super-sampling implementations. Using a RGSS technique, quality, however, was extremely high. As seen, with 4x AA, anything over 1024x768 overflows the 64MB of available memory, making it impossible to store the necessary buffers. With 2x AA, this overflow occurs at 1280x1024.
Quake 3 Ė16x Anisotropic filtering
Anisotropic performance was fairly consistent, showing little degradation. When compared to bilinear performance levels, the change is actually rather small. This can be attributed to the use of dynamic filtering levels, as well as ATIís use of a bilinear anisotropic filter.
Quake 3 Ė 16x Anisotropic filtering/4xAA
With anisotropic filtering having such a minimal performance impact, as was expected, using anisotropic with anti-aliasing had minimal impact on performance when compared to simply using anti-aliasing alone.
Performance: For a low-end board, as with Radeon 9000 Pro, performance is fairly impressive. Each successive generation of low-end products definitely raises the bar for what one considers low-end. Historically, low-end products had out-of-date feature sets and under-par performance. Yet, with RV250 based boards, such as Tachyon, the latest DirectX feature set is supported and performance is more than adequate.
Memory: While 64 MB of memory is adequate, when it comes to using high resolutions, and especially anti-aliasing, it simply doesnít cut it. Anti-aliasing quickly consumes available memory, reducing the amount of potential texture memory.
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