Reviews | Gigabyte GeForce 9800GT 512MB (Page 2 of 10)

Page 2 - NVIDIA 9800GT Architecture

The hardened thermal interface material with quite a bit of adhesive force is really hard to get off.

Manufacturer: NVIDIA
Series: GeForce 9
GPU Core, Process: G92, 65nm / G92b, 55nm * Not with this particular review unit
Interface: PCI-E 2.0 (Backwards compatible)
Core Clock (Stock): 600 MHz
Shader Clock (Stock): 1500 MHz
Memory Clock (Stock): 900 MHz (1800 DDR)
Memory Bandwidth: 57.6 GB/sec
Shader Operations: 168000 MOperations/sec
Pixel Fill Rate: 9600 MPixels/sec
Texture Fill Rate: 33600 MTexels/sec
Memory Type: GDDR3
Memory Bus Type: 64x4 (256 bit)
DirectX Compliance: 10.0
OpenGL Compliance: 2.1
PS/VS Version: 4.0/4.0
Shader Processors: 112
Pipeline Layout: Scalar MADD+MUL
Texture Units: 56
Raster Operators: 16
Data above courtesy of GPUReview.com.

The heart of the NVIDIA GeForce 9800GT is NVIDIA's recycled G92 core that's used in, well, quite a bit of cards. The 9800GT is essentially identical to the 8800GT; as manufacturers are permitted to directly flash a 8800GT to a 9800GT. Meanwhile, 'real' 9800GTs has added support for HybridPower and 3-way SLI, as well as a revised 55nm G92b core for better overclockability and thermal management. Our Gigabyte 9800GT has the original 65nm G92 core, as seen in the photo above.

Architecturally speaking, the package NVIDIA puts forth in the G92 65nm 9800GT graphics card is really a derivative of the 90nm G80 core, rather than the 80nm based G84 used on the 8600 series -- identical to the original 8800GT. At 65nm, the original G92 core implements a good chunk of complexity in terms of transistors -- integrating 754 million as juxtaposed to G80's 681 million transistors. The G80 based 8800GTS has 96 active stream processors, whereas the 8800GT/9800GT has it increased to 112 with 56 texture address units and 56 texture units (1:1 ratio). The stream processors are also clocked high at 1.5GHz that clocks as high as the 8800 Ultra. Keep in mind, however, the 8800GTX based off the G80 core still has 128 stream processors as the 8800GTS G80 has 32 of those disabled.

The 65nm process has the die surface shrunk down approximately 33% to 324 mm² from 484 mm² even with much more transistors on board. With that taken into account, there's still a reduction in SPs, texturing power, and not as many ROPs as its higher G80 relatives, but still more shader and texture horsepower than he 8800GTS G80. Anyway, the ROPs are cut down to 16 as the G80 8800GTS actually had 20 on board. The NVIDIA 8800GT and 9800GT has a texture fill rate of 33.6 billion/second.

On the other hand, compression algorithm of the ROPs has been improved for insanely high resolutions with the G92 (As well as the the G92b, quite literally a die shrunk G92) over the G80. This may not mean much in terms of 3D graphics acceleration for gaming purposes, simply due to the fact that the 9800GT is not powerful enough to run most games at 30" LCD monitor resolutions anyway. The 8800GTS G92/9800GTX in SLI may benefit, but other than that -- this architectural enhancement may mean less to the end user.

Additional features added back onto the 9800GT, like the 8800GT, is the native support of dual HDCP dual link DVI output, instead of using a separate display chip. NVIDIA PureVideo 2 hardware video decoding replaces NVIDIA PureVideo on the previous generation G80 cores; which has demonstrated superior hardware decoding performance as compared -- results are seen floating around articles with NVIDIA PureVideo 2 performance on G84 based video cards such as the 8500 and 8600 series. PCIe 2.0 support is implemented as well; despite that this will have no real definition with regards to performance even on PCIe 2.0 boards that offers additional bandwidth, this evolutionary step is also fully backwards compatible.

One step back from the G80 generation cards is its 256 bit memory interface with a memory bandwidth of 57.6GB/s as compared to the 8800GTS G80's 320 bit memory interface offering up to 64GB/s.

The Gigabyte GeForce 9800GT 512MB clocks the core at stock 600MHz; with memory at 900MHz actual (1800MHz effective clock) -- again, stock. It should be mentioned that the memory on the 9800GT are the same Samsung chips utilized in the Gigabyte 8800GT TurboForce 512MB. Since this is really a stock 8800GT (Or 9800GT, if your must), it should score slightly lower in our performance benchmarks than the compared factory overclocked edition 8800GT cards.


Page Index
1. Introduction, Specifications, Bundle
2. NVIDIA 9800GT Architecture
3. A Closer Look, Test System
4. Benchmark: FEAR
5. Benchmark: Prey
6. Benchmark: Half Life 2: Lost Coast
7. Benchmark: CS:Source HDR
8. Benchmark: 3DMark06
9. Power Usage, Overclocking
10. Noise Factor and Conclusion