IBM says it will begin sampling its new IBM PowerPC 750GX microprocessor next month, the next generation of the "G3" processor. Based on the PowerPC 750FX processor, the new chip uses IBM"s advanced 0.13-micron copper process with Silicon-on-Insulator technology and will be offered at frequencies up to 1.1GHz. The 750GX includes 1MB of internal L2 cache, 4-way set-associative, additional L1 and L2 cache buffers for pipelining of up to four data cache miss operations, and support for up to 200MHz operation of the 60x system bus interface with additional bus pipelining. IBM"s PowerPC 750FX is used in currently shipping iBooks at speeds up to 900MHz. Production is targeted for December 2003.
According to the June 2003 edition of IBM Processor news, the integrated 1MB of L2 cache operates at the processor"s core frequency, providing minimal latency for instruction fetch operations and data load operations that hit in the L2 cache. The larger size of the internal L2, twice that available on the 750FX, provides more on-chip memory storage for application code and data, and may provide a significant performance improvement, due to the size alone, according to IBM. In addition, the L1 data cache path to the Bus Interface Unit (BIU) and the L2 cache reload path to the L1 data cache are now 256-bits wide.