It's been only about seven weeks since the GeForce 7800 GTX was officially launched on June 22, but NVIDIA is already making news yet again today with the latest addition to their GeForce 7 Series of cards, the new GeForce 7800 GT. As its name implies, the GeForce 7800 GT is very similar to NVIDIA's current flagship GeForce 7800 GTX, but the GT is launching with a significantly lower MSRP for a couple of reasons. Both cards are based on the GPU formerly codenamed "G70", however, the GeForce 7800 GT has four less pixel pipelines and is missing one vertex unit when compared to the GTX version. The new GeForce 7800 GT's reference specifications also call for lower core and memory clock speeds than the GeForce 7800 GTX, but we don't think NVIDIA's reference specifications are going to be followed by their board partners. The XFX card that we tested for this article surely didn't.
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GeForce 7800 GT Specifications |
The GTX's Little Brother |
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Click Any Image For An Enlarged View
NVIDIA CineFX 4.0 Shading Architecture
•_Vertex Shaders
·_Support for Microsoft DirectX 9.0 Vertex Shader 3.0
·_Displacement mapping
·_Geometry instancing
·_Infinite length vertex programs
•_Pixel Shaders
·_Support for DirectX 9.0 Pixel Shader 3.0
·_Full pixel branching support
·_Support for Multiple Render Targets (MRTs)
·_Infinite length pixel programs
•_Next-Generation Texture Engine
·_Accelerated texture access
·_Up to 16 textures per rendering pass
·_Support for 16-bit floating point format and 32-bit floating point format
·_Support for non-power of two textures
·_Support for sRGB texture format for gamma textures
·_DirectX and S3TC texture compression
•_Full 128-bit studio-quality floating point precision through the entire rendering pipeline with native hardware support for 32bpp, 64bpp, and 128bpp rendering modes
API Support
• Complete DirectX support, including the latest version of Microsoft DirectX 9.0 Shader Model 3.0
•_Full OpenGL support, including OpenGL 2.0
64-Bit Texture Filtering and Blending
•_Full floating point support throughout entire pipeline
•_Floating point filtering improves the quality of images in motion
•_Floating point texturing drives new levels of clarity and image detail
•_Floating point frame buffer blending gives detail to special effects like motion blur and explosions
NVIDIA Intellisample 4.0 Technology
•_Advanced 16x anisotropic filtering (with up to 128 Taps)
•_Blistering- fast antialiasing and compression performance
•_Gamma-adjusted rotated-grid antialiasing removes jagged edges for incredible image quality
•_Transparent multisampling and transparent supersampling modes boost antialiasing quality to new levels
•_Support for normal map compression
•_Support for advanced lossless compression algorithms for color, texture, and z-data at even higher resolutions and frame rates
•_Fast z-clear
NVIDIA UltraShadow II Technology
•_Designed to enhance the performance of shadow-intensive games
NVIDIA Digital Vibrance Control (DVC) 3.0 Technology
•_DVC color controls
•_DVC image sharpening controls
NVIDIA SLI Technology
•_Patented hardware and software technology allows two GPUs to run in parallel to scale performance
•_Scales performance on over 60 top PC games and applications |
NVIDIA PureVideo Technology
•_Adaptable programmable video processor
•_High-definition MPEG-2 and WMV9 hardware acceleration
•_Spatial-temporal de-interlacing
•_Inverse 2:2 and 3:2 pull-down (Inverse Telecine)
•_4-tap horizontal, 5-tap vertical scaling
•_Overlay color temperature correction
•_Microsoft Video Mixing Renderer (VMR) supports multiple video windows with full video quality and features in each window
•_Integrated HDTV output
Composited Desktop Hardware Engine
•_Video post-processing
•_Real-time desktop compositing
•_Accelerated antialiased text rendering
•_Pixel shader-driven special effects and animation
Advanced Display Functionality
•_Dual integrated 400MHz RAMDACs for display resolutions up to and including 2048x1536 at 85Hz
•_Dual DVO ports for interfacing to external TMDS transmitters and external TV encoders
•_Full NVIDIA nView multi-display technology capability
Advanced Engineering
•_Designed for PCI Express x16
•_Designed for high-speed GDDR3 memory
Operating Systems
•_Windows XP/XP 64/ME/2000
•_Linux
•_Macintosh OS X
The GeForce 7800 GT GPU:
Front View
The GeForce 7800 GT GPU:
Underside View
An entire wafer of G70s... |
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Due to the fact that the new NVIDIA GeForce 7800 GT GPU is based upon the same core architecture as the GeForce 7800 GTX, it shares essentially the same feature set as its higher-powered counterpart. We've detailed NVIDIA's latest architecture in-depth in our original coverage of the GeForce 7800 GTX launch back in June, so we'd recommend perusing that article if you're not familiar with what the GPU formerly code named G70 brings to the table. On top of everything offered by NVIDIA's previous flagship GeForce 6800 Ultra (NV40), the G70 GPU incorporates new anti-aliasing modes in the Intellisample 4.0 engine that improve the appearance of partially transparent textures, such as those used in many outdoor scenes for foliage. The G70 also has an updated dedicated video processor, dubbed PureVideo, with more features than its predecessor. And of course, the G70 has enhancements to its pixel and vertex shader pipelines for increased performance, as well.