What's new
What's new?
We took a detailed look at the GeForce 8800 GTX's architecture here, and I'd urge you to refresh your memory if G80's basic setup has become a blur.Spilling the expected beans, NVIDIA's invested so much money into architecting GeForce 8800 that adding much else than clock bumps will prove to be too expensive, so let's trot out the spec. table to do the talking.
| Graphics Cards | NVIDIA GeForce 8800 Ultra 768 | NVIDIA GeForce 8800 GTX 768 | NVIDIA GeForce 8800 GTS 640 | NVIDIA GeForce 8800 GTS 320 | AMD Radeon X1950 XTX 512 |
|---|---|---|---|---|---|
| GPU clock | 612MHz | 575MHz | 500MHz | 500MHz | 648MHz |
| Shader clock | 1500MHz | 1350MHz | 1200MHz | 1200MHz | 648MHz |
| Memory clock (effective) | 2160MHz | 1800MHz | 1600MHz | 1600MHz | 2000MHz |
| Memory interface, size, and implementation | 384-bit, 768MiB, GDDR3 | 320-bit, 640MiB/320MiB, GDDR3 | 256-bit, 512MiB, GDDR4 | ||
| Memory Bandwidth | 103.68GB/sec | 86.40GB/sec | 64.00GB/sec | ||
| Manufacturing process | TSMC, 90nm (90HS) | ||||
| Transistor Count | 681M | 384M | |||
| DirectX Shader Model | 4.0 | 3.0 | |||
| Vertex Shading | 128 FP32 scalar ALUs, MADD+MUL dual-issue (Unified) | 8 vec4 + scalar ALUs, MADD co-issue | |||
| Fragment Shading | 128 FP32 scalar ALUs, MADD+MUL dual-issue (Unified) | 48 vec3 + scalar ALUs, MADD+ADD dual-issue | |||
| Geometry Shading | 128 FP32 scalar ALUs, MADD+MUL dual-issue (Unified) | N/A | |||
| Data Sampling and Filtering | 32ppc address and 64ppc bilinear INT8 filtering, max 16xAF | 16ppc address and 16ppc bilinear INT8 filtering, max 16xAF | |||
| ROPs | 24, 8Z or 8C samples/clk, 2clk FP16 blend 8xMSAA, 16xCSAA |
20, 8Z or 8C samples/clk, 2clk FP16 blend 8xMSAA, 16xCSAA |
16, 2Z or 1C samples/clk, 2clk FP16 blend 6xMSAA |
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Put simply, the GeForce 8800 Ultra is a faster-clocked version of GeForce 8800 GTX. NVIDIA's bumped up the core speed by just over 6 per cent, shader clocks by around 11 per cent and memory bandwidth by 20 per cent. Each of these increases will become telling when playing games at ultra-high resolutions and with added image quality. We'd expect the Ultra to be around 10 per cent faster than the GTX in most card-limited scenarios. It also means that the Ultra packs in 576GFLOPS of compute performance at default shader speeds!
The Ultra's speed increase is reasonable if not pant-wettingly exciting, especially the core's meagre increase. NVIDIA's G80 yields have improved over the last 6 months and we've seen AIBs ship a slew of overclocked, air-cooled GTXs that run with near-Ultra speeds and, in cases, watercooling. NVIDIA's documentation asserts that the Ultra utilises a 'new silicon revision and advanced process enhancements', meaning a general clean-up of the 90nm design by removing some of the slower paths and improving general timings: tweaks, if you will.
It's patently obvious that the GeForce 8800 Ultra will usurp the GTX and become the fastest graphics card around, and we'll have to wait a short while for AMD's riposte before declaring it the performance champion of H1 2007.
Pricing
NVIDIA understands that the well-heeled enthusiast will hanker for the fastest GPU around, almost irrespective of price; even if that entails a small performance upgrade from the incumbent GeForce 8800 GTX.| Graphics Cards | NVIDIA GeForce 8800 Ultra 768MiB | NVIDIA GeForce 8800 GTX 768MiB | NVIDIA GeForce 8800 GTS 640 | NVIDIA GeForce 8800 GTS 320 | AMD Radeon X1950 XTX 512 |
|---|---|---|---|---|---|
| RRP pricing as at 02/05/07 | $829+/£499 | $599+/£350+ | $399+/£250+ | $299+/£175+ | $379/£225 |
NVIDIA's GeForce 8800 Ultra pricing reflects the fact that it believes its SKU will be faster than anything produced by AMD. That why it's happy to charge such a premium for a SKU that should have no single-card performance peer. We reckon the $829 U.S. Dollar pricing will be reflected by a U.K. retail price of around £499. Expensive, yes, but that's the price you for ultimate performance which has a natural upgrade path (SLI - £1000).
