The 25th incarnation of Siggraph, the premier computer-graphics show held last month in Orlando, Fla., proved that it's time to cast aside conventional wisdom about where advanced workstations and 3-D software are headed.

First off, forget the notion that the only battle is between Windows NT and Unix. Indeed, the workstation proving ground is rapidly shifting from operating systems and CPUs to the graphics subsystem. Sure, the likes of Intel, Sun and Compaq are talking up their respective Xeon, UltraSparc II and Alpha processors. But show-floor demos proved the latest 3-D accelerators can often tip the balance, pushing the benchmarks of otherwise comparable systems over the top.

Perhaps the boldest foray into new accelerator territory came from Intergraph Computer Systems, which launched its Wildcat 3D architecture at the show. Wildcat is a scalable technology that Intergraph claims can bring Silicon Graphics-class graphics to desktop workstations. Evans & Sutherland, SGI and Hewlett-Packard also weighed in with accelerator offerings.

Armed with such tools, the major workstation vendors are waging an intense battle for market share. The nastiest fight is for the hearts and minds of the creators of digital content in Hollywood, TV and the post-production studio. As SGI defends its turf, Sun and HP are launching new, aggressive bids for these markets.

However, as hardware horsepower ramps up, everyone's concerned about a looming software question. Namely, who will control the key software APIs for workstations? To the industry's terror, the answer appears to be Microsoft.

In tandem with SGI, Microsoft is developing Fahrenheit, an API that will combine Microsoft's Direct3D and DirectDraw and SGI's OpenGL technology.

Sources in the Unix world worry because Fahrenheit doesn't now run on Sun or IBM workstations. They fret about what kind of licensing terms Microsoft will offer and whether Fahrenheit will be a true cross-platform technology.

A final critical issue is the apparent contention brewing between the IBM group in Austin, Texas, which develops graphics-accelerator technology for the company's Unix workstations, and IBM's PC graphics team in Pittsburgh. "They're not really technologists," a source close to the Unix team told me. "They just go and see what they can buy off-the-shelf." He also complained of trying to develop cutting-edge technology with one hand tied behind his back. "We're not funded in such a way that we can take a leadership role," he said. "And our research group has lost a lot of people."