PowerPC 603

The PowerPC 603 is the second series of PowerPC processors used by Apple Computer, largely in PowerPC-based models of their consumer-oriented Macintosh Performa line. Versions of the 603 were also used by Be Inc. in their BeBox. These processors were developed by the AIM alliance, which included Apple, IBM, and Motorola.

Development history
The PowerPC 603 was designed to be lower cost and more power efficient than the preceding PowerPC 601, making it suitable for consumer computer models. It also contained a built-in 32-bit floating point unit. However, early versions were criticized for poor performance. Later versions improved considerably and eventually evolved into the PowerPC G3.

Processors

 * PowerPC 603 — featured an 8KB instruction cache and 8KB data cache, smaller than the unified 32KB L1 cache used by the PowerPC 601. One major side effect was that Gary Davidian's original Mac 68k emulator would not fit into 8KB of cache memory, severely hampering performance when running older applications written for the Motorola 68000 series. This was only used in the Power Macintosh 6200 and 5200 LC, which were both noted for poor performance. It was also used in Bandai's Pippin game consoles. The use of a dynamic recompiler can help offset some of the cache limitations.
 * PowerPC 603e — featured a larger 16KB instruction cache and 16KB data cache, for improved performance. Introduced in the Power Macintosh 5260 and 6300, 603e processors were also used throughout Apple's early PowerPC-based PowerBook line.
 * PowerPC 603ev — higher speed versions (180 MHz and above) introduced in the Power Macintosh 5400 and 6400.