NVIDIA Takes a New Stab at the Mainstream with GeForce 6600

Introduction

NVIDIA has high hopes to gain share in the mainstream segment with its launch of the GeForce 6600, based on the processor code-named NV43. While NVIDIA is not yet supplying test samples because of some last-minute changes to the board design, the prospects for the card's success do not look so bad, based on its specs. Meanwhile, we can offer a few facts on NVIDIA's latest product offering for the mainstream market before we get the card in our labs for a comprehensive set of benchmarking tests.

NVIDIA GeForce 6600 Product Rundown

NVIDIA puts all it's got into Doom III. Even the GeForce 6600 is supposed to be way ahead of the competition.

The new graphics processor that powers the GeForce 6600, codenamed NV43, is based on a 110-nm process and shares the architecture of the NV40 processor, which is the processor for the previously-launched GeForce 6800 card. The 3D feature list of the GeForce 6600 entirely matches that of the GeForce 6800:

• DirectX 9.0c support with shader model 3.0;
• Rotated grid FSAA (IntelliSample 3.0);
• Ultra shadow II;
• 32-bit floating point precision;
• 64-bit texture filtering and blending;
• GDDR3 memory (on GeForce 6600 GT);
• On-chip video processor;
• 400 MHz Ramdac.

With 146 million transistors, the NV43 has become quite complex.

In contrast to earlier product generations, in which NVIDIA cut back significantly on technical capability to save money in some cases, the savings are limited in the case of the NV43 to the number of pixels and vertical pipelines. Instead of 16 (6800 Ultra/GT) or 12 (6800), the new GeForce 6600 is equipped with just 8 pixel pipelines. NVIDIA has reduced the number of vertex shader units from 6 to 3. The width of the memory bus has also been cut from 256-bit to 128-bit. NVIDIA estimates the number of transistors at 146 million.

The GeForce 6600 is the first graphics card from NVIDIA to have a native PCI Express interface. On its market launch, only the PCI Express version will be initially available. It will be followed a little later by the AGP 8x version, which is equipped with NVIDIA's HSI bridge chip. This is where the dual-track layout of the HSI chip pays off, because NVIDIA does not have to provide a new processor for the AGP version.

There are currently two versions of the NV43 scheduled: The GeForce 6600 "GT" and the 6600 without additional qualification. There are no plans for an "Ultra" version, because NVIDIA wants to use this name only in the enthusiasts' segment in future.