Intel released the first Pentium D products (codenamed "Smithfield") on May 26,
2005, with clock speeds of 2.8, 3.0, and 3.2 GHz. The chips carried model numbers of
820, 830 and 840 respectively. An 805, clocked at 2.66 GHz with a 533 MT/s bus,
appeared in early 2006.
Smithfield is made on a 90nm process with 1MiB of L2 cache per core. The
Smithfield Pentium D does not support Hyper-Threading, although similar Pentium
Extreme Edition counterparts do. Smithfield does not support VT, Intel's virtualization
feature formerly called Vanderpool.
The Pentium D processor supports Intel's EM64T technology, the XD Bit and like
most current Pentium 4s, uses the LGA775 form factor on an 800 MT/s bus. The only
motherboards guaranteed to work with the Pentium D (and Extreme Edition) are those
based on the 945, 955 and 975 series of chipsets, as well as the nForce 4 SLI Intel
Edition. The Pentium D 820 won't work with the nForce 4 SLI Intel Edition due to some
power design issues, though they were rectified for the X16 version of the chipset.
Motherboards based on the 915 and 925 series of chipsets will not work at all, as the
chipsets do not have support for more than one processor core (a result of Intel trying to
prevent motherboard manufacturers making Xeon motherboards with the chipsets, as
happened with the 875P). The 865 and 875 series chipsets do have multiprocessor
support, so motherboards based on these chipsets may be Pentium D compatible, so long
as the manufacturer provides an appropriate BIOS update.
As with a multiprocessor PC, the Pentium D provides significant performance
improvement only with applications that have been written specifically for multiple
CPUs or cores — such as most 3D rendering programs and video encoders — and in
heavy multitasking situations where the PC user is running several CPU-heavy
applications, and each core can handle a different application. Most business applications
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and games as of 2005 only use a single thread, so for these applications running alone,
the Pentium D will deliver largely the same performance as an older Pentium 4 running at
the same clock rate. However, applications rarely run alone on PCs running Linux, BSDfamily,
or Microsoft Windows operating systems.
After a week of confusion following the processor's launch, Intel officially denied
a report in Computerworld Today Australia that the Pentium D includes "secret" digital
rights management features in hardware that could be utilized by Microsoft Windows and
other operating systems, but was not publicly disclosed. While it admitted that there were
some DRM technologies in the 945 and 955 series of chipsets, it stated that the extent of
the technologies was exaggerated, and that the technologies in question had been present
in Intel's chipsets since the 875P.
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