Hardware Reference
In-Depth Information
similar course. Sempron identifies Socket A processors based on the Athlon XP as well as Socket
754, 939, AM2, and AM3 processors based on the Athlon 64 and 64 X2.
The Socket A version of the AMD Sempron is based on the Athlon XP processor, whereas the Socket
754, 939, AM2, and AM3 versions are based on the Athlon 64. Sempron X2 models are dual-core
processors based on the Athlon X2. The difference is that the Sempron versions are offered in lower
processor and bus clock speeds, with smaller caches and sometimes limited features to justify a
lower price point.
Because AMD has offered Sempron processors in many distinctive variations, it's easy to get
confused as to which is which and what features are included in a specific model. By looking up the
processor on the AMD Desktop Processor Comparison website (
http://products.amd.com/en-
us/DesktopCPUResult.aspx
), you can find out the exact specification, including socket type, vo
ltage,
revision, cache size, and other information about the chip. You can also use software tools, such as
CPU-Z (
www.cpuid.com
), to find more detailed information about a given processor.
AMD Athlon X2, 64 X2, and 64 FX
The 64-bit Athlon 64 processors were designed with multicore updates in mind from the beginning.
The desktop Athlon 64 X2 was introduced in May 2005. The Athlon 64 X2 uses several core designs,
with different options and features.
The following are major features of the Athlon 64 X2:
• 65nm or 90nm manufacturing process
• Actual clock speeds of 1.9GHz-3.0GHz
• Socket 939, AM2, and 1207FX form factors
• 1GHz HyperTransport interconnect (4GBps bandwidth)
The design of these processors has always included room for the second processor core along with a
crossbar memory controller to enable the processor cores to directly communicate with each other
without using the North Bridge, as with Intel's initial dual-core processors.
Figure 3.41
illustrates the
internal design of the Athlon 64 X2.
