Firingsquad heeft een review gepost van de nieuwe PowerMac G4. Helaas hebben ze nog geen benchmarks (die komen hopelijk later), wel wat theoretische info over de werking van de G4 en z'n Altivec SIMD engine, waar Steve zo fanatiek op loopt te hypen:
How's AltiVec compare to MMX, 3D-Now, and SSE? Well, MMX is a joke. It always been considered more hype than substance, so I won't even compare them. SSE and 3D-Now are pretty much comparable to each other, although 128-bit vs. 64-bit registers give SSE the advantage. AltiVec kicks both their butts however. Why? Partly because the AltiVec is a newer implementation with more and better instructions. However, it is mostly because of the number of available SIMD registers. SSE has 8 registers available for it, while AltiVec has 32.
For the uninitiated, registers are the locations on the processor that hold the numbers being played around with. For most instructions, data has to be brought in from the memory or cache to the register before being manipulated. This is true with integer and floating-point operations as well as SIMD. Less registers means that a Pentium III will run out of data to process faster than a G4. It also makes it more difficult to do complex calculations that involve more than 8 x 128-bits of data. This prob