NVIDIA GeForce 8800 GT - G92 Takes Flight
NVIDIA’s G92 Architecture, A New GPU For The GeForce 8800 GT
Below is an easy to digest table of specifications for various members of NVIDIA's G8 series of GPUs and their associated reference board build-outs. Here you'll be able to more easily place where the new GeForce 8800 GT should fall, in terms of overall performance and capabilities.
| GeForce 8800 Ultra | GeForce 8800 GTX |
GeForce 8800 GTS 640MB |
GeForce 8800 GT 512MB | |
| GPU Core Clock |
612MHz | 575MHz | 500MHz | 600MHz |
| GPU Shader Clock |
1500MHz | 1350MHz | 1200MHz | 1500MHz |
| Memory Interface Clock | 1080MHz (2160MHz DDR) |
900MHz (1800MHz DDR) |
800MHz (1600MHz DDR) |
900MHz (1800MHz DDR) |
| Fill Rate |
39.2 GT/s |
36.8 GT/s | 24 GT/s | 33.6 GT/s |
| Memory Bandwidth |
103.6GB/s | 86.4 GB/s |
64 GB/s | 57.6 GB/s |
| Stream Processors |
128 | 128 | 96 | 112 |
| Memory Interface |
384-bit | 384-bit | 320-bit | 256-bit |
| Fab Process |
90nm | 90nm | 90nm | 65nm |
| Number of Transistors |
681M | 681M | 681M | 754M |
| Street Price or MSRP | $615 street | $520 street | $380 street | $199 - $249 MSRP |
OK, we know what you're thinking, 754M transistors with goosed up core clock and memory clocks that compete a GeForce 8800 GTX but this is a "mid-range" card. And you'd be correct. As the saying goes, today's high-end will be tomorrow's mid-range, so to speak. But there's more to the picture here than the numbers really show. With 112 Stream Processors and a 256-bit memory interface, the new GeForce 8800 GT offers higher overall fill-rate than a GeForce 8800 GTS but slightly less memory bandwidth, though some third party board partners may offer higher speed variants versus the reference design. From a pure fill-rate perspective, the new GeForce 8800 GT should come within striking distance of a GeForce 8800 GTX but at a fraction of the cost, thanks in part to that 65nm die shrink.
If the above block diagram looks vaguely familiar, it's because it is. What you're looking at is the same basics block layout of the NVIDIA G80 architecture but with only seven groups of 16 Steam processor units. 7 times 16 equates to 112 total stream processors. So we have our basic math in check here but why the odd number of SP units? Good question. The simple fact is that this new GPU core is more or less a die shrink of the existing G80 minus one SP unit, or at least one of the 8 available on the original G80 core has been disabled. However, in the immortal words of a cheesy infomercial host, but wait, there's more! NVIDIA brought new features and engine enhancements to the GeForce 8800 GT and we'll dig into those next.
