Hardware Reference
In-Depth Information
Figure 1-12.
The Intel Core i7-3960X die. The die is 21 by 21 mm and has 2.27
billion transistors. © 2011 Intel Corporation. Used by permission.
the Celeron has the same architecture as the Pentium 2, we will not discuss it fur-
ther in this topic. In June 1998, Intel introduced a special version of the Pentium 2
for the upper end of the market. This processor, called the
Xeon
, had a larger
cache, a faster bus, and better multiprocessor support but was otherwise a normal
Pentium 2, so we will not discuss it separately either. The Pentium III also had a
Xeon version as do more recent chips. On more recent chips, one feature of the
Xeon is more cores.
1n 2003, Intel introduced the Pentium M (as in Mobile), a chip designed for
notebook computers. This chip was part of the Centrino architecture, whose goals
were lower power consumption for longer battery lifetime; smaller, lighter, com-
puters; and built-in wireless networking capability using the IEEE 802.11 (WiFi)
standard. The Pentium M was very low power and much smaller than the Pentium
4, two characteristics that would soon allow it (and its successors) to subsume the
Pentium 4 microarchitecture in future Intel products.
All the Intel chips are backward compatible with their predecessors as far back
as the 8086. In other words, a Pentium 4 or Core can run old 8086 programs with-
out modification. This compatibility has always been a design requirement for
Intel, to allow users to maintain their existing investment in software. Of course,
