All the cache you need
The L3 cache uses 2MB of high-speed, Double Data Rate (DDR) SDRAM running at a data rate of up to 500MHz. The L3 cache boosts processor function by providing fast access to data and application code at speeds of up to 4 gigabytes per second (GBps). And the L3 cache is even more effective at speeding up processing because it has a dedicated bus to the G4 chip, making the full 4GBps data throughput always available - unimpeded by bottlenecks caused by other data (unlike Pentium 4-based systems, which don't have L3 cache - a disadvantage that leads to congestion between various data streams, and slowdowns in the overall rate of data transfer).
The high speed L3 cache with its dedicated bus enables the PowerPC G4 processor to receive data up to five times faster than it could from main memory. This low latency keeps the processors constantly fed with data, so it isn't idling while waiting for the next task to arrive. The L3 cache is large enough to store active application code and data. When you run an application, most of the active code for the program ó along with most of the data being used ó is in L3 cache. Thus the information most required by the processor is close at hand. It's analogous to the caching of web pages on your hard disk drive: Click the back button on your web browser, and your computer will use the data you loaded two pages ago ó skipping the step of reloading the same data again ó making the page appear quicker.
