Visiontek Radeon X1300 256MB PCI review
While the vast majority of us these days are happily using machines with PCI Express, or at least AGP, capabilities, giving us opportunities to boost our graphics performance more or less at will, spare a thought for those who are less fortunate than ourselves. Although it's now thankfully becoming less commonplace, you can still find cheap, pre-built systems in this day and age which come sans any kind of graphics upgradeability, with no PCI Express 16x or AGP slot in sight.
Until recently there has been no road for such users to traverse in search of some additional GPU goodness. But now, in a rather surprising move in all honesty, a couple of ATI's AIB partners have come to the rescue, courtesy of PCI-based Radeon X1300 boards. Of course, the RV515 core which powers the Radeon X1300 utilises a PCI Express interface natively, meaning that such boards require the use of a bridge chip to sit between the core and the PCI bus for data transfers.
One such partner which has offered up this functionality to the masses is Visiontek, and today we'll be taking a look at the 256MB Radeon X1300 PCI board. Will it be crippled by the transfer rates of this ancient bus, or can it offer a new lease of life for users with no other upgrade options when it comes to gaming and video playback? Read on to find out.
Radeon X1300 architecture
In its most basic terms, you could quite easily consider the RV515 core that powers the Radeon X1300 as simply quarter of an R520, due to its featuring a single quad of pixel pipelines complemented by four texturing units (compared to four quads of pipelines and sixteen texture processors on R520) and two vertex shaders (against eight in R520). Each pixel shader unit within the core has the same ALU configuration and abilities as the rest of the Radeon X1000 series. The Ultra Threaded Despatch Processor used by R520 is also present in RV515, but again its abilities are a quarter those of its big brother, with it being capable of processing 128 threads here compared to 512 in R520 and R580.
One area where RV515 does miss out over its more powerful siblings is with regard to the memory controller - The ring bus controller used in RV530/RV535, R520 and R580 is absent here (no doubt due to the massive amount of die space it occupies), replaced by a more traditional crossbar controller which is 64-bits in width in this instance.
In terms of feature support the X1300 is largely identical to the rest of the Radeon X1000 series, from Shader Model 3.0 capabilities down to the ability to perform floating-point blending (with multi-sample anti-aliasing no less!). The X1300 also features the same anti-aliasing and anisotropic filtering abilities of the rest of the family, including the rotationally invariant 'High Quality' mode. Indeed, compared to R520, RV515 actually holds one feature over it - Fetch 4, present on all ATI's current product line-up aside from the Radeon X1800, makes an appearance here too. If you want to read more about the functionality of Fetch 4, take a look at our Radeon X1900 XTX review. The Radeon X1000 series architecture itself is covered in more detail here.
You can see the entire feature set of the Radeon X1300 below.
- Ultra Threaded Shader Engine
- Support of DirectX9 Programmable Vertex and Pixel Shaders
- VS3.0 Vertex Shader functionality
- 1024 Instructions (Unlimited with flow control)
- Single Cycle Trigonometric Operations (SIN & COS)
- PS3.0 Pixel Shaders
- Ultra Thread Pixel Shader Engine
- Fast Dynamic Branching
- Single Precision 128-bit Floating Point (FP32) Processing
- 16 textures per rendering pass
- 32 temporary and constant registers per pixel
- Facing register for two-sided lighting
- Multiple render target support
- Shadow volume rendering acceleration
- 128-bit, 64-bit & 32-bit per pixel floating point colour formats
- Advanced Image Quality Features
- HDR Blending on FP16, Int10 and Custom Formats
- All Blending modes work with all Anti-Aliasing Modes
- 3Dc+ Normal Map Compression
- High quality 4:1 Normal Map Compression
- Two Channel & Single Channel format support
- 2x/4x/6x Multi-Sampling full scene Anti-Aliasing modes, adaptive algorithm with programmable sample patterns and colour buffer compression
- Adaptive Anti-Aliasing for Transparent Surfaces
- Temporal Anti-Aliasing
- Lossless Color Compression (up to 6:1) at all resolutions, including widescreen HDTV resolutions
- High Quality, Angle Invariant, Anisotropic Filter Mode
- 2x/4x/8x/16x Anisotropic Filtering modes
- 4Kx4X texture Support
- HDR Blending on FP16, Int10 and Custom Formats
- Memory Controller
- Internal Ring Bus Architecture (RV530)
- Programmable Arbitration Logic
- Fully Associative Caches
- 3-level, Floating Point, Hierarchical Z-Buffer with early Z test
- Lossless Z-Buffer compression (up to 48:1)
- Fast Z-Buffer Clear
- Z Cache Optimisations for shadow rendering
- Optimized for performance at high display resolutions, including widescreen HDTV resolutions
- Dual 10-bit Display Pipelines
- Dual Integrated Dual Link TMDS Transmitters, Dual 400MHz RAMDACS, Xilleon Derived TV Output.
- Hardware Accelerated H.264 Decode