User`s manual

Introduction
Page 1-5
Pentium 4 also introduces a 400/533MHz system bus as opposed to the 100 and
133MHz bus seen in previous Pentium III processors. This allows 3.2Gbytes per
second of throughput while the Pentium III had a limited 1.06Gbyte/s throughput.
Willamette will reportedly be introduced in the 0.18-micron using aluminum.
For more information about all the cool new features the Pentium 4 delivers
check out the Intel website at
http://www.intel.com
Direct Rambus
The Direct Rambus (RDRAM) initiative will provide the memory bandwidth
necessary to obtain optional performance from the Pentium 4 or later 478-pin
socket processor as well as a high-performance AGP graphics controller. The
MCH RDRAM interface supports 400/533MHz operation; the latter delivers
3.2/4.2GB/s of theoretical memory bandwidth; twice the memory bandwidth of
100/133MHz SDRAM system. Coupled with the greater bandwidth, the RDRAM
protocol, which is heavily pipelined, provides substantially more efficient data
transfer. The RDRAM memory interface can achieve greater than 95% utilization
of the 3.2/4.2GB/s theoretical maximum bandwidth. The Figure 1 is the example
picture for RIMM Module to plug in the RIMM socket.
Figure 1: RIMM Module