From Voodoo Graphics to VSA-100 and beyond

[Carsten]

3Dfx Voodoo 2 with SLI

(This posting is still in beta-stage, information herein not confirmed and exhaustive!)

On November 3rd 1997, 3Dfx introduced the new generation of Voodoo via press release and scheduled an estimated availability for Q1 1998. The Voodoo 2 improved on its predecessor in a number of ways. Functionally, nothing very significant was added to the architecture with 3D performance being the main concern at that time and rightly so! Manufactured in 350 instead of Voodoo Graphics' 500 nm process tech, 3dfx was able to bump the clock speeds significantly to 90 MHz. Additionally, every Voodoo 2 card was outfitted with two texture chips (each with its own 2-4 MiByte of texture memory) making for a multi-textured fillrate of about 180 MTexels/sec. Thus Voodoo 2 was able to to multi-texturing at almost quadruple (more precisely: 3,6x) the rate of Voodoo Graphics.



Due to the larger default frame buffer, a single Voodoo 2 was able to accelerate games using a z-buffer in resolutions up to 800x600. Paired with a like card in Scan Line Interleave mode (for short SLI), where each card would do only half the vertical resolution, this was increased to a then might 1024x768.

The continued support for 3dfx proprietary Glide API provided customers with a usable base of dozens of accelerated games which would automatically benefit from the higher graphics power. Compatibility issues due to the larger memories were rare, but present. Third party tools soon offered a work around limiting the adressable memory for a given game to Voodoo Graphics levels.

The whole press release is shown at www.thefreelibrary.com and here's the interesting part:

SAN JOSE, Calif., Nov. 3 /PRNewswire/ -- 3Dfx Interactive today announced plans for the introduction of their new standard in 3D acceleration, Voodoo 2 Graphics(TM). A generational leap beyond the Company's original award winning Voodoo Graphics chipset, Voodoo 2 will be available at the consumer level in the first Quarter of 1998 and will retail for under $300.

Voodoo 2 is an expandable architecture with a base configuration of a 192-bit memory architecture and 2.2 Gigabytes per second of memory bandwidth, delivering over 50 BOPS (Billions of Operations per Second). This configuration delivers an incredible 3 million triangles per second and 90 million dual-textured, bilinear-filtered, per-pixel MIP-mapped, alpha-blended, Z-buffered pixels per second, over three times the performance of the current Voodoo Graphics. Voodoo 2 contains a full floating-point hardware triangle setup unit for maximum triangle throughput on Pentium, Pentium Pro and Pentium II powered systems. Voodoo 2 is also an AGP-capable technology designed to utilize the higher bandwidth available through AGP and will support 3D games with resolutions up to 1024 X 768.

"We believe that Voodoo 2 will not only change the way people play games, but the way that people design games," said Greg Ballard, President and CEO, 3Dfx Interactive. "The original Voodoo Graphics and Voodoo Rush chipsets opened people's eyes to the possibilities of 3D gaming and the response has been overwhelming. We have once again set the standard by which all other 3D accelerators will be judged."

Since Voodoo 2 maintains full software compatibility with Microsoft's Direct3D, 3Dfx's Glide and OpenGL, current 3Dfx accelerated games will run on the new chipset. This new level of technology will not require the end user to purchase new software, as the current catalog of over 150 3Dfx enhanced titles will not only run on Voodoo 2, but will receive a noticeable improvement in performance.

Two technologies developed specifically for 3Dfx's arcade customers have now been made available to PC game players. The basic chipset for Voodoo2 contains two texture processing units that simultaneously apply two textures to a triangle for single-pass, single-cycle rendering of effects such as trilinear filtering, sophisticated lighting, spotlights and detail texturing. Dual texture units effectively double the texture fill rate and provide dramatic performance increases in games such as id Software's Quake and Quake 2, which will run upwards of 110 frames per second.

Customers will also be able to purchase a second board of the same type and connect the two for even faster gameplay. Voodoo 2 will automatically detect a second chipset and will begin operating in Scanline Interleave mode, where the first chipset draws the even scanlines of a frame while the second chipset draws the odd, reducing the amount of work per chipset by half and allowing each card to run at twice the speed. This high-end configuration expands to a 384-bit memory architecture with 4.3 Gigabytes per second memory bandwidth, achieving an amazing 180 million pixels per second.

Contrary to the claims made in the press release, all publicly available cards didn't come in AGP flavor and thus weren't able to utilize the modern graphics port. The 192 Bit memory bus mentioned in the press release consists of three separate 64 bit wide connections. One for the fixed 4 MiByte framebuffer and one for each of the two texture units' 2-4 MiBytes.

3Dfx Voodoo 2
Codename	SST-96 (notes: SST probably stands for Scott-Sellers-Tarolli, the founders of 3Dfx)
Type	3D add-on card, no 2D functionality
Year	1997 (announced), 1998 (released)
Manufacturing Technology	350 nm
No. of transistors	1 Million per chip
Pixel throughput	1 Pixel per clock
Texel throughput	2 Texel per clock (board level)
Z/Depth throughput	1 Zixel per clock
Core Clock rate	90 MHz
Memory Clock rate	90 MHz
Memory Data rate	90 MT/sec.
Memory	4 MiByte Framebuffer + 2-4 MiByte Texture Memory for eacht of the two texture units
Memory Interface	3x 64 Bit (one for Framebuffer, two for Texture Memory)
Supported 3D-Features	Perspective Correction, Bilinear Filtering, Alpha Blending, Z-Buffer, Gouraud Shading, Multi-Texturing
Supported Resolutions	320x240, 512x384, 640x400, 640x480, 800x600, 1024x768 (single board without Z-Buffer)
Multi-Chip configuration	SLI, adding a second board connected via internal cable could double the theoretical figures and greatly improve 3D performance as well as enabling 1024x768 as generally usable 3D resolution

Currently, I own two of these boards (and a rather special one), one being the Creative Labs 3D Blaster Voodoo² (internal model no. CT6670). It is the fully equipped consumer version with a total of 12 MiBytes of video memory (EtronTech EM614163A-25) and a fairly standard model in every respect.



The other Voodoo 2 card according to the rather excellent ressource database at falconfly.de comes in from CMC and is called Orbit 3D (internal model no FQI3DFXV2). It is also equipped with 12 MiByte grand total memory (EliteMT M11B416256A M3462-UA -25J). No bells and wihstles on this one either.



Last but not least, I am one of the lucky persons to own a Quantum 3D board: It is called Obsidian2 SLI2 X24 and basically incorporates two 12 MiByte Voodoo2 cards on one single card albeit with two PCBs. In order to remove excessive heat beween the two planes, a fan is mounted at the right of the very long base PCB and blow air inbetween the PCBs. In total there are six chips (two framebuffer chips and 2x2 texture chips) working teamed up to render the image. 24 MiByte of EDO-RAM (Silicon Magic R9822 SM81C2256K16CJ-25, specced at 100 MHz) were an enourmous amount for that time. The cards works, but needs a special adapter cable called Medusa, which I do not have.