the GCI have 650-0001-00x on the PCB

so i should be the first product

650 = 3dfx
210 = STB
middel four gets higher with the time
00x is the rev
001 rev A
002 rev B
003 rev C

afaik,the whole idea behind 3dfx was bringing the graphics from arcade machines to the consumer pc..


edit: ok,so I was wrong..

Hi ! this article was originaly written in french and I suppose there is a google translation if you don't understand what about it is takling...
As it is one o'clock and i just return from the pub, let's me try to do a translation that you'll understand.

O"n March 27 of the following year, 3Dfx Interactive was bring to life with a capital of 5,5 millions US $.
At the time of his creation, 3Dfx goal was to make PC graphics cards and interfaces system for Arcade gaming machine, because at this time theses systems (arcade machine) were considered far much powerfull and better plateform for gaming than PC.
Despite this fact, firsts 3Dfx products were already compatible with the PC world : the technology used PCI BUS, and some pieces allowed to connect arcade gaming's controls on a PC.
One of the first product known is the JAMMA Game-Control-Interface GCI : it translates signals from a Arcade Gaming system on a RS232 signal witch is understood by a PC. That was realized by using a microchip from Intel  (80C51)

I hope my translation is easier for you to understand.
So since his creation 3dfx goal was to make 3D graphics cards, but it was more profitable in 1994 - 1995 to make Arcades chip...

By the way I've read a lot of time this article, there is plenty of mistake (VSA 101 to get more power, 3dfx acquired by nVidia, Quantum 3D wasn't a split of 3dfx etc.)

Thanks guys, that did help.