Launched on April 14, 2004, the GeForce 6 family introduced PureVideo post-processing for video, SLI technology, and Shader Model 3.0 support (compliant with Microsoft DirectX 9.0c specification and OpenGL 2.0).

The Scalable Link Interface (SLI) allows two GeForce 6 cards of the same type to be connected in tandem.

SM3 extends SM2 in a number of ways: standard FP32 (32-bit floating-point) precision, dynamic branching, increased efficiency and longer shader lengths are the main additions.

[3] In addition, motherboards with some VIA and SIS chipsets and an AMD Athlon XP processor seemingly have compatibility problems with the GeForce 6600 and 6800 GPUs.

Problems that have been known to arise are freezing, artifacts, reboots, and other issues that make gaming and use of 3D applications almost impossible.

Yet, the 6800 Ultra was fabricated on the same (IBM) 130 nanometer process node as the FX 5950, and it consumed slightly less power.

Nvidia added support for the PCI Express (PCIe) bus in later GeForce 6 products, usually by use of an AGP-PCIe bridge chip.

Later, when Nvidia's GPUs were designed to use PCIe natively, the bidirectional bridge chip allowed them to be used in AGP cards.

ATI, initially a critic of the bridge chip, eventually designed a similar solution (known as Rialto[4]) for their own cards.

User and web reports showed little if any difference between PureVideo enabled GeForces and non-Purevideo cards.

The prolonged public silence of Nvidia, after promising updated drivers, and test benchmarks gathered by users led the user community to conclude that the WMV9 decoder component of the AGP 6800's PureVideo unit is either non-functional or intentionally disabled.

[citation needed] In late 2005, an update to Nvidia's website finally confirmed what had long been suspected by the user community: WMV-acceleration is not available on the AGP 6800.

Of course, today's computers are fast enough to play and decode WMV9 video and other sophisticated codecs like MPEG-4, H.264 or VP8 without hardware acceleration, thus negating the need for something like PureVideo.

With half the pixel pipelines and vertex shaders of the 6800 GT, and a smaller 128-bit memory bus, the lower-performance and lower-cost 6600 is the mainstream product of the GeForce 6 series.

Notably, the 6600 GT offered identical performance to ATI's high-end X800 PRO graphics card with drivers previous December 2004, when running the popular game Doom 3.

The term GeForce 6100/6150 actually refers to an nForce4-based motherboard with an integrated NV44 core, as opposed to a standalone graphics card.

Nvidia released this product both to follow up its immensely popular GeForce4 MX based nForce and nForce2 boards and to compete with ATI's RS480/482 and Intel's GMA 900/950 in the integrated graphics space.

A class action suit was filed against HP and Nvidia by Whatley Drake & Kallas LLC.

Its onboard video outperforms the 6150 in many 3D benchmarks despite its lower core frequency (425 MHz), because of added hardware Z-culling.

These new antialiasing modes enhance the image quality of thin-lined objects such as fences, trees, vegetation and grass in various games.

Because of this, Nvidia had to backport IntelliSample 4.0 features to the NV4x GPUs, and as a result, the entire GeForce 6 family is able to enjoy the benefits of Transparency Antialiasing.