Nvidia has officially unveiled the GeForce3 chip set, previewed by Apple CEO Steve Jobs during his keynote speech at Macworld Conference and Expo, Tokyo.

Nvidia has released more details regarding the chipset, which boasts the programmable NfiniteFX engine and "competes favourably" with ATI's high-end Radeon product.

GeForce3 will appear as a build-to-order option for Power Macs in March, and a version of the chip set is booked for use in Microsoft's forthcoming Xbox game console.

Clock speeds It offers a 200MHz core clock speed - the same as that of the GeForce2 GTS, but slower than the 250MHz of the GeForce2 Ultra. Its memory clock speed is the same as that of the Ultra. But, its smaller .15-micron design, more-efficient graphics handling, and huge host of transistors - 57 million, more than twice that of the GeForce2 GTS -make it a much faster chip set than any in the GeForce2 line.

These new and faster chips don't just speed up frame rates and increase screen resolution, they can also use effects that make objects look better, such as the GeForce3's high-resolution antialiasing.

Antialiasing removes the jagged edges of graphical objects to provide a smoother image, but the process can also slow performance to the point that many users turn off the feature. The GeForce3 promises nearly four times the speed of the GeForce2 Ultra in antialiasing.

Flexible engine The GeForce3 also stands out because of the flexibility of its NfiniteFX engine. Since the engine is programmable, developers can create lighting effects and custom looks for screen objects and backgrounds instead of being forced to choose from a limited set.

John Carmack, lead programmer at Id software and the brains behind the first-person shooters Doom and Quake, praises the chip.

"The short answer is that the GeForce3 is fantastic," says Carmack. "I haven't had such an impression of raising the performance bar since the Voodoo2 came out, and there are a ton of new features for programmers to play with."

The capabilities of the GeForce3 mirror those supported by Microsoft's DirectX 8 application programming interface, says product manager Ballew. "We worked with Microsoft to define it, and we will work with Microsoft to refine it," he says.