Power Macintosh: Memory Interleaving Performance Gain (6/96)

Article Review/Updated: 27 June 1996

Is there any information available on the performance gains or losses when using interleaved instead of non-interleaved memory on PCI-based Power Macintosh computers?

Specifically how much of a speed advantage would be lost if you use one 16 MB DIMM rather than two 8 MB DIMMs in an interleaved arrangement?
For increased performance it is better to configure a PCI-based Power Macintosh computer for memory interleaving rather than installing memory in a non-interleaved configuration. This means that you will get better performance if you configure your system with two 16 MB DIMMs rather than one 32 MB DIMM. This applies to all other combinations of same-sized DIMMs.

The actual performance will vary from computer to computer. In general, a Power Macintosh with a PowerPC 604 microprocessor, such as the Power Macintosh 8500 or 9500 series computer, gets anywhere from a 5% to 15% boost in performance. The average is about an 8% increase in performance speed. On a Power Macintosh with a PowerPC 601 microprocessor, such as the Power Macintosh 7500 series, you may get only a slightly better performance gain by using memory interleaving rather than non-interleaved DIMMs. Some third-party benchmarking applications may report exaggerated performance differences between interleaved and non-interleaved computers.

This article was published in the Information Alley on 26 June 1996.

Article Change History:
27 Jun 1996 - Added keyword.
26 Jun 1996 - Made minor correction.
10 May 1996 - Added information about exaggerated benchmarking results.



Published Date: Feb 19, 2012