Strategy

The Katmai 600 finished the 100-MHz front-side bus series. Taking a cue from the overclocking community, Intel slid the Katmai to a 133-MHz front-side bus rating. This new series is marked by the addition of a B modifier to each model's speed rating.

Still suffering from the .25-micron core design, the Katmai 533B provides modest overclocking potential. Perhaps worse than the processor's core limitation is the lack of support for extended front-side bus speeds in the popular 133-MHz-capable Slot 1 boards. After VIA introduced its Apollo Pro133A chipset, support for motherboard rates beyond 133 MHz began to appear in the mainstream markets. Intel released its own i815 and i820 chipsets and the latter of these offered RAMBUS memory support.

Most Katmai 533B chips can successfully overclock to 560 MHz. The retail Intel heatsink should be adequate; a core voltage increase of 0.1 volts is usually all that is required. Any increase in the front-side bus rate can offer significant performance returns through increased memory bandwidth when the memory subsystem is operating at or above the processor bus rate. The popular VIA Pro133A chipset introduced support for down-clocking memory, using asynchronous signaling. Benchmarking will measure the performance gains, assuming memory down-clocking is employed to attain a higher front-side bus speed.