Hardware Reference
In-Depth Information
The various models and features of the Athlon 64 and 64 FX are summed up in
Table 3.21
.
Table 3.21. Athlon 64 and 64 FX Processor Information
The Athlon 64 and 64 FX were available in four socket versions, the core features of which are
detailed in
Table 3.22
. Note that Socket 940 supports only slower and more expensive registered
DIMMs.
Table 3.22. AMD Athlon 64 and 64 FX Socket and Memory Types
The Athlon 64 essentially comes in three versions: a Socket 754 version that has only a single-
channel memory bus, an improved Socket 939 version that has a dual-channel memory bus, and an
even better Socket AM2 version that has a dual-channel DDR2 bus. The Athlon 64 FX is also
available in three versions: a Socket 940 version that uses expensive (and slower) registered
memory, an improved Socket 939 version that uses unbuffered memory, and an updated version that
uses dual-channel DDR2. The Socket 939 versions of the Athlon 64 and 64 FX are essentially the
same chip, differing only in the amount of L2 cache included. For example, the Athlon 64 3800+ and
Athlon 64 FX-53 both run at 2.4GHz and run dual-channel memory. The only difference is that the
3800+ has only 512KB of L2 cache, whereas the FX-53 has 1MB of L2 cache. Because the 64 and 64
FX chips are essentially the same, you need to read the fine print to determine the minor differences
in configuration.
The Athlon 64 FX can draw up to 104W or more of power, which is high but still somewhat less than
the more power-hungry Pentium 4 processors. As with the Pentium 4, motherboards for the Athlon 64
and 64 FX generally require the ATX12V connector to provide adequate 12V power to run the
processor voltage regulator module.
The initial version of the Athlon 64 is built on a 0.13-micron (130-nanometer) process. Subsequent
versions use either a 0.09-micron (90nm) or a .065-micron (65nm) process.
AMD Sempron
AMD introduced the Sempron line of processors in 2004 as a replacement for the Duron brand and to
provide an economy line of processors designed to compete with the Intel Celeron D. Just as the Intel
Celeron name long ago ceased to identify a particular processor and instead is a brand that identifies
various types of low-cost, reduced-performance processors, AMD's Sempron brand follows a
