The core (cont’d)

CineFX 2.0

Besides the addition of UltraShadow technology, NVIDIA has improved upon its CineFX architecture first introduced with GeForce FX 5800. NVIDIA has optimized all stages of the pixel pipeline in CineFX 2.0. According to NVIDIA, CineFX 2.0 doubles the floating-point pixel shading power of GeForce FX 5800. This should result in a dramatic performance boost, as pixel shader programs can be executed more quickly.

NVIDIA claims this improvement gives them an edge over RADEON 9800 PRO, 3,600 floating-point shader ops in GeForce FX 5900 Ultra versus 3,040 in RADEON 9800 PRO.

Intellisample HCT

Intellisample HCT is NVIDIA second generation of compression and caching technology, and has been redesigned for optimal performance with GeForce FX 5900’s new 256-bit memory interface. NVIDIA has introduced new algorithms that are more successful at compressing texture, color and Z data than Intellisample 1.0, resulting in improved antialiasing performance at high resolutions.

NVIDIA has also introduced a new 8x antialiasing mode in its latest driver, and improved the aniostropic filtering quality as well. We’ll be discussing these topics further in this article.

The 3D engine

The remainder of GeForce FX 5900’s engine remains unchanged from GeForce FX 5800. This means that the same 4-pixel pipeline architecture with two texture units per pipe (4x2) that caused so much controversy earlier this year is still used. ATI on the other hand has implemented eight pixel pipelines with one texture unit per pixel pipeline (8x1) in its RADEON 9700, 9800 series. ATI is also proud to proclaim that it has one more vertex engine than NVIDIA.

With GeForce FX 5900 Ultra’s 450MHz clock frequency, this means that there may be some cases where the GeForce FX 5800 Ultra actually outperforms it. GeForce FX 5800 Ultra sports a fill-rate of 2 Gigapixels/sec (500MHz core clock x 4 pixel pipelines), versus 1.8 Gigapixels/sec (450MHz core x 4 pipes) in GeForce FX 5900 Ultra. In comparison, RADEON 9800 PRO boasts just over 3 Gigapixels/second. The GeForce FX cards will have an advantage over ATI in multi-texturing, as the 5800 Ultra’s theoretical fill-rate is 4 Gigatexels/sec and the 5900 Ultra’s is 3.6 Gigatexels/sec. Meanwhile the RADEON 9800 PRO’s peak fill rate is 3.04 Gigatexels/sec.

GeForce FX 5900 variants

NVIDIA plans to produce three GeForce FX 5900 variants: the GeForce FX 5900 Ultra 256MB (the board we’re testing today), a 128MB GeForce FX 5900, and a 128MB value solution. The 256MB 5900 Ultra board will ship in June with an estimated selling price of $499. The middle GeForce FX 5900 part will also ship in June but with reduced clock frequencies and a $399 price tag. To avoid confusion, hopefully NVIDIA will use the “Pro” designation to denote these cards.

The value GeForce FX 5900 will be a cost-reduced version of the GeForce FX 5900 128MB (our “Pro”) with even lower clocks and will ship later this summer (one slide from NVIDIA’s presentation stated July) at a list price of $299. Shots of this board provided by NVIDIA look similar to the GeForce FX 5600 Ultra reference board.