Comparison to Athlon 64 X2
The competing Athlon 64 X2, although running at lower clock rates and lacking Hyper-threading, had some significant advantages over the Pentium D, such as an integrated memory controller, a high-speed HyperTransport bus, a shorter pipeline (12 stages compared to the Pentium D's 31), and better floating point performance,[11] more than offsetting the difference in raw clock speed. Also, while the Athlon 64 X2 inherited mature multi-core control logic from the multi-core Opteron, the Pentium D was seemingly rushed to production and essentially consisted of two CPUs in the same package. Indeed, shortly after the launch of the mainstream Pentium D branded processors (26 May 2005) and the Athlon 64 X2 (31 May 2005), a consensus arose that AMD's implementation of multi-core was superior to that of the Pentium D.[12][13] As a result of this and other factors, AMD surpassed Intel in CPU sales at US retail stores for a period of time, although Intel retained overall market leadership because of its exclusive relationships with direct sellers such as Dell.[14]
Comparison to Pentium Dual-Core
In 2007, Intel released a new line of desktop processors under the brand Pentium Dual Core, using the Core microarchitecture (which was based upon the Pentium M architecture, which was itself based upon the Pentium III). The newer Pentium Dual-Core processors give off considerably less heat (65 watt max) than the Pentium D (95 or 130 watt max). They also run at lower clock rates, only have up to 2 MB L2 Cache memory while the Pentium D has up to 2x2 MB, and they lack Hyper-threading.
The Pentium Dual-Core has a wider execution unit (four issues wide compared to the Pentium D's three) and its 14 stages-long pipeline is less than half the length of the Pentium D's, allowing it to outperform the Pentium D in most applications despite having lower clock speeds and less L2 cache memory.
