Editing Pentium D

{{Short description|Family of Intel microprocessors}}
{{distinguish|Pentium Dual-Core}}
{{Infobox CPU
| name        = Pentium D
| image       = Intel Pentium D Logo.png
| image_size  = 138px
| caption     = Logo as of 2006
| produced-start = {{Start date and age|2005|05|25}}
| produced-end = {{End date and age|2010|07|13}}<ref>{{cite web |title=Product Change Notification, 107779 - 00 |url=https://qdms.intel.com/dm/i.aspx/B5883E95-206A-481F-8A33-A81B6E7F14D7/PCN107779-00.pdf |publisher=Intel |year=2007}}</ref>
| slowest     = 2.66  | slow-unit     = GHz
| fastest     = 3.73  | fast-unit     = GHz
| fsb-slowest = 533  | fsb-slow-unit = MT/s
| fsb-fastest = 1066  | fsb-fast-unit = MT/s
| manuf1      = Intel
| core1       = Smithfield
| core2       = Presler
| size-from   = 90&nbsp;nm
| size-to     = 65&nbsp;nm
| arch        = [[x86-64]]
| microarch   = [[NetBurst]]
| sock1       = [[LGA 775]] (Socket T)
| numcores    = 2 (2×1)
| predecessor  = {{ubl|[[Pentium 4]]|[[Pentium 4 HT]]}}
| successor  = {{ubl|[[Intel Core 2|Core 2]] (2006)|[[Pentium Dual-Core]] (2007)}}
| support status = Unsupported
|soldby=Intel|designfirm=Intel|code=Smithfield: 80551<br/>Presler: 80553|l2cache=2–4 MB|l1cache=32 KB (16 KB (8 KB instructions + 8 KB data) x 2)|instructions=[[MMX (instruction set)|MMX]], [[Streaming SIMD Extensions|SSE]], [[SSE2]], [[SSE3]]|cpuid=0F47h (Smithfield)<br/>0F65h (Presler)|transistors1=Smithfield: 176 million|transistors2=Presler: 376 million|extensions1=[[SpeedStep|EIST]], [[VT-x]]|application=Dual-core desktop}}
'''Pentium D'''<ref>{{cite web |title=The Pentium D: Intel's Dual Core Silver Bullet Previewed |date=5 April 2005 |url=https://www.tomshardware.com/reviews/pentium-d,1006.html |publisher=Tom's Hardware |access-date=2007-07-08}}</ref> is a range of desktop 64-bit [[x86-64]] processors based on the [[NetBurst]] microarchitecture, which is the [[Multi-core processor|dual-core]] variant of the [[Pentium 4]] manufactured by [[Intel]]. Each [[CPU]] comprised two cores. The brand's first processor, codenamed Smithfield and manufactured on the [[90 nm process]], was released on May 25, 2005, followed by the [[65 nm]] Presler nine months later.<ref>{{cite web |title=The 65 nm Pentium D 900's Coming Out Party: Test Setup |url=http://www.tomshardware.com/2006/01/05/the_65_nm_pentium_d_900s_coming_out_party/page6.html |publisher=Tom's Hardware |access-date=2007-07-04}}</ref> The core implementation on the 90 nm Smithfield and later 65 nm Presler are designed differently but are functionally the same. The 90 nm Smithfield contains a single [[Die (integrated circuit)|die]], with two adjoined but functionally separate CPU cores cut from the same [[wafer (electronics)|wafer]]. The later 65 nm Presler utilized a [[multi-chip module]] package, where two discrete dies each containing a single core reside on the CPU substrate. Neither the 90 nm Smithfield nor the 65 nm Presler were capable of direct core to core communication, relying instead on the [[Northbridge (computing)|northbridge]] link to send information between the two cores.

By 2004, the NetBurst processors reached a [[clock speed]] barrier at 3.8&nbsp;GHz due to a thermal (and power) limit exemplified by the Presler's 130 watt [[thermal design power]]<ref name="toms-p5"/> (a higher TDP requires additional cooling that can be prohibitively noisy or expensive). The future belonged to more energy efficient and slower clocked [[dual-core]] CPUs on a single die instead of two.<ref>{{cite web |title=Intel Moves From Dual Core To Double Core: 65 nm Intel Double Core Preslers Forward |date=10 October 2005 |url=https://www.tomshardware.com/reviews/intel-moves-dual-core-double-core,1142.html |publisher=Tom's Hardware |access-date=2007-08-05}}</ref> However, the Pentium D did not offer significant upgrades in design,<ref>{{cite web |title=The 65 nm Pentium D 900's Coming Out Party: The 65 nm NetBurst |url=http://www.tomshardware.com/2006/01/05/the_65_nm_pentium_d_900s_coming_out_party/index.html |publisher=Tom's Hardware |access-date=2007-08-05}}</ref> still resulting in relatively high power consumption.<ref name="toms-p5">{{cite web |title=The 65 nm Pentium D 900's Coming Out Party: Thermal Design Power Overview |url=http://www.tomshardware.com/2006/01/05/the_65_nm_pentium_d_900s_coming_out_party/page5.html |archive-url=https://archive.today/20120702232159/http://www.tomshardware.com/2006/01/05/the_65_nm_pentium_d_900s_coming_out_party/page5.html |url-status=dead |archive-date=July 2, 2012 |publisher=Tom's Hardware |access-date=2007-08-05 }}</ref>

The final shipment date of the dual die Presler chips was August 8, 2008,<ref>{{cite web |title=Intel intros 3.0 GHz quad-core Xeon, drops Pentiums |url=http://www.tgdaily.com/content/view/33351/135/ |publisher=TG Daily |access-date=2007-08-14 |archive-date=2007-09-26 |archive-url=https://web.archive.org/web/20070926231529/http://www.tgdaily.com/content/view/33351/135/ |url-status=dead }}</ref> which marked the end of the Pentium D brand and also the NetBurst microarchitecture. The Pentium D line was removed from the official price lists on July 13, 2010.

==Pentium D/Extreme Edition==
[[File:Intel Pentium D 930 with i945GC chipset.jpg|thumb|300px|Pentium D 930 (Presler) with Intel 945GC chipset]]
The dual-core CPU is capable of running [[Multithreading (computer architecture)|multi-threaded]] applications typical in [[transcoding]] of audio and video, [[Data compression|compressing]], photo and [[Video editing software|video editing]] and [[Rendering (computer graphics)|rendering]], and [[Ray tracing (graphics)|ray-tracing]]. Single-threaded applications, including most older games, do not benefit much from a second core compared to an equally clocked single-core CPU. Nevertheless, the dual-core CPU is useful to run both the client and server processes of a game without noticeable lag in either thread, as each instance could be running on a different core. Furthermore, multi-threaded games benefit from dual-core CPUs.

In 2008, many business applications were not optimized for multiple cores. They ran at similar speed when not multitasking on the Pentium D or older [[Pentium 4]] branded CPUs at the same clock speed.{{citation needed|date=December 2013}} However, in [[Computer multitasking|multitasking]] environments such as [[Berkeley Software Distribution|BSD]], [[Linux]], [[Microsoft Windows]] operating systems, other processes are often running at the same time; if they require significant CPU time, each core of the Pentium D branded processor can handle different programs, improving overall processing speed over its single-core Pentium 4 counterpart.
{| class="wikitable"
|+Intel Pentium D processor family
|-
! rowspan="2" |Original
logo
! rowspan="2" |2006
logo
! colspan="3" |Desktop
|-
!Code-named
!Node
!Date released
|- style="background:white"
|[[Image:Pentium d lg.png|100px|Pentium D logo as of 2005]]
|[[Image:Intel Pentium D Logo.png|100px|Pentium D logo as of 2006]]
|Smithfield<br>Presler
|90&nbsp;nm<br>65&nbsp;nm
|May 2005<br>Jan 2006
|- style="background:white"
|[[Image:Pentium Extreme Edition.jpg|100px|Original Pentium Extreme Edition logo]]
|[[Image:Intel Pentium Extreme Edition Logo.png|100px|Pentium Extreme Edition logo as of 2006]]
|Smithfield XE<br>Presler XE
|90&nbsp;nm<br>65&nbsp;nm
|May 2005<br>Jan 2006
|-
! colspan="5" |<small>[[List of Intel Pentium D processors]]</small>
|}

=== Smithfield ===
[[Image:Pentium d 820.jpg|thumb|180px|Underside of a Pentium D 820]]
In April 2005, Intel's biggest rival, [[AMD]], had x86 [[dual-core]] processors intended for [[workstation]]s and [[Server (computing)|server]]s on the market, and was poised to launch a comparable product intended for [[desktop computer]]s. As a response, Intel developed Smithfield, the first x86 dual-core processor intended for desktop computers, beating AMD's [[Athlon 64 X2]] by a few weeks. Intel first launched Smithfield on April 16, 2005 in the form of the 3.2 GHz [[Hyper-threading]] enabled ''Pentium Extreme Edition 840''. On May 26, 2005, Intel launched the mainstream Pentium D branded processor lineup with initial clock speeds of 2.8, 3.0, and 3.2&nbsp;GHz with model numbers of 820, 830, and 840 respectively. In March 2006, Intel launched the last Smithfield processor, the entry-level Pentium D 805, clocked at 2.66&nbsp;GHz with a 533 [[Megatransfer|MT/s]] bus. The relatively cheap 805 was found to be highly [[overclock]]able; 3.5&nbsp;GHz was often possible with good [[air cooling]]. Running it at over 4&nbsp;GHz was possible with [[water cooling]], and at this speed the 805 outperformed the top-of-the-line processors (May 2006) from both major CPU manufacturers (the AMD ''[[Athlon 64]] FX-60'' and Intel ''Pentium Extreme Edition 965'') in many benchmarks including power consumption.<ref>{{cite web |title=A 4.1 GHz Dual Core at $130 - Can it be True?|date=10 May 2006 |url=http://www.tomshardware.com/reviews/dual-41-ghz-cores,1253.html|access-date=2007-07-30}}</ref>

The 805 and 820 models had a 95 watt [[Thermal Design Power|TDP]]. All other models were rated at 130 watt.

All Smithfield processors were made of two 90 nm [[Pentium 4#Prescott|Prescott]] cores, next to each other on a single [[Die (integrated circuit)|die]] with 1 MB of [[L2 cache|Level 2 (L2) cache]] per core. Hyper-threading was disabled in all Pentium D 8xx-series Smithfields with the exception of the ''Pentium Extreme Edition 840''. Smithfield did not support [[Intel VT-x]]—Intel's [[x86 virtualization]] (formerly Vanderpool).

All Pentium D processors supported [[Intel 64]] (formerly EM64T), [[XD Bit]], and were manufactured for the [[LGA 775]] form factor. The only [[motherboard]]s guaranteed to work with the Pentium D (and Extreme Edition) branded CPUs were those based on the 945-, 955-, 965- and 975-series [[List of Intel chipsets|Intel chipsets]], as well as the [[NForce4|nForce 4 SLI Intel Edition]] and [[Xpress 200|ATI Radeon Xpress]]. The Pentium D 820 did not work with the nForce 4 SLI Intel Edition chipset due to some power design issues, though they were rectified in the X16 version. The 915- and 925-series chipsets did not work at all with the Smithfields, as they did not support more than one core (to prevent manufacturers making a cheap dual CPU motherboard capable of supporting [[Xeon]] CPUs, as had happened with the 875P chipset). The 865- and 875-series chipsets supported multiprocessing. Motherboards with them might be Pentium D compatible with an updated [[BIOS]].

A week after its launch, Intel officially denied a report<ref>{{cite web |title=Intel quietly ships Pentium D with DRM |url=http://www.computerworld.com.au/article/133031/intel_quietly_ships_pentium_d_drm |publisher=Computer World Australia |access-date=2009-10-13}}</ref> in ''Computerworld Today Australia'' that the Pentium D branded CPUs included "secret" [[digital rights management]] features in their hardware that could be utilized by [[Microsoft Windows]] and other operating systems, but was not publicly disclosed. While Intel admitted that there were some DRM technologies in the 945- and 955-series 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.

===Smithfield XE===
The Pentium Extreme Edition (PXE) was introduced at the Spring 2005 Intel Developers Forum, not to be confused with the "[[Pentium 4#Northwood (Extreme Edition)|Pentium 4 Extreme Edition]]" (an earlier, single-core processor occupying the same niche). The processor was based on the dual-core Pentium D branded Smithfield, but with [[Hyper-threading]] enabled, thus any operating system saw four logical processors. It also had an unlocked multiplier to allow for easier overclocking. It was initially released as Intel Pentium Extreme Edition 840 at 3.20&nbsp;GHz, in early 2005, at a price point of $999.99 ([[Original equipment manufacturer|OEM]] price) or $1,200 (retail). The only chipsets that worked with the Extreme Edition 840 were Intel's 955X, NVIDIA's nForce4 SLI Intel Edition, and ATi Radeon Xpress 200. Using a Pentium Extreme Edition branded CPU with an Intel 945-series chipset will disable Hyper-threading.

=== Presler ===
[[File:Intel Pentium D 930 3.00GHz.jpg|thumb|Intel Pentium D 930 3.00GHz on an Intel D945GCCR motherboard]]
The last generation of Pentium D branded processors was Presler released on January 16, 2006, identified by the product code 80553, and made of two [[65 nm process]] cores found also in [[Pentium 4]] branded [[Pentium 4#Cedar Mill|Cedar Mill]] CPUs. Presler introduced the multi-chip module, or MCM, which consisted of two single-core [[Die (integrated circuit)|dies]] placed next to each other on the same substrate package. This allowed Intel to produce these processors at a reduced production cost as a result of higher yields. Presler was supported by the same chipsets as Smithfield. It was produced using 65 nm technology similar to [[Yonah (microprocessor)|Yonah]]. Presler communicated with the system using an 800 MT/s [[Front-side bus|FSB]], and its two cores communicated also using the FSB, just as in Smithfield. Presler also included [[Intel VT-x]] (formerly Vanderpool) &ndash; although this was limited to the 9x0 models, and not in the 9x5 models&ndash; [[Intel 64]], [[XD bit]], and Enhanced Intel [[SpeedStep]] Technology (EIST). Presler was released in the first quarter of 2006 with a 2×2 MB Level&nbsp;2 cache. Its models included 915, 920, 925, 930, 935, 940, 945, 950 and 960 (with a respective 2.8, 2.8, 3.0, 3,0, 3.2, 3.2, 3.4, 3.4, and 3.6&nbsp;GHz clock frequency).

All steppings of Presler models 915, 920, 925, 930, and 935, as well as the C1, D0 steppings of 940, 945 featured a 95 watt [[Thermal Design Power|TDP]]. All other models (i.e. certain models with 3.2&nbsp;GHz or faster clock frequencies) were rated at 130 watt — a 37% increase in power consumption.<ref>{{cite web |title=The 65 nm Pentium D 900's Coming Out Party: Thermal Design Power Overview |url=http://www.tomshardware.com/2006/01/05/the_65_nm_pentium_d_900s_coming_out_party/page5.html |archive-url=https://archive.today/20120702232159/http://www.tomshardware.com/2006/01/05/the_65_nm_pentium_d_900s_coming_out_party/page5.html |url-status=dead |archive-date=July 2, 2012 |publisher=Tom's Hardware |access-date=2007-07-04 }}</ref>

[*] The first batch of Presler processors (revision B1) had the [[EIST]] feature turned off by a microcode update because of stability issues. That affected only its power consumption, when idle, and thermal dissipation. Chips with working EIST started shipping in Q2 2006. They had a different S-Spec number which can be found in Intel errata documentation.

===Presler XE===
The Pentium Extreme Edition based on the dual-core Pentium D branded Presler was introduced as the 955 model, at 3.46&nbsp;GHz, and used a 1066 [[Megatransfer|MT/s]] FSB compared to the 800 MT/s in the non-Extreme edition. A second version, the 965 at 3.73&nbsp;GHz followed in March 2006. Both CPUs also feature Hyper-Threading Technology and an unlocked multiplier. Overclockers have been able to overclock the core to 4.26&nbsp;GHz using air cooling simply by raising the unlocked CPU multiplier.

The Presler Extreme Edition was intended to only be combined with the Intel 975X chipset, it could also work with the 955X chipset, though this combination was not supported by Intel. The i975X featured the [[I/O Controller Hub#ICH7|ICH7R]] southbridge and supported all [[LGA 775]] (Socket T) Pentium 4, Pentium D, and Pentium Extreme Edition branded processors.

== Successor==
{{main|Intel Core 2}}
The Pentium D brand was merged with the [[Pentium 4]] brand and succeeded on July 27, 2006, by the [[Core 2]] branded line of processors with the [[Core (microarchitecture)|Core microarchitecture]] released as dual- and quad-core processors branded Duo, Quad, and Extreme.

== Implementation ==
In a single-processor scenario, the [[CPU]]-to-[[northbridge (computing)|northbridge]] link is [[Point-to-point (telecommunications)|point-to-point]] and the only real requirement is that it is fast enough to keep the CPU fed with data from [[RAM|memory]].

When assessing the Pentium D, it is important to note that it is essentially two CPUs in the same package and that it will face the same [[bus contention]] issues as a pair of [[Xeon]]s prior to the Dual Independent Bus architecture introduced with the Dual-Core Dempsey Xeons. To use a crude analogy one could say that instead of using a single cable between CPU and north bridge, one must use a Y-splitter. Leaving aside advanced issues such as [[cache coherency]], each core can only use half of the 800 MT/s [[Front-side bus|FSB]] bandwidth when under heavy load.

== Comparison to Athlon 64 X2 ==
The competing AMD [[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 [[instruction pipelining|pipeline]] (12 stages compared to the Pentium D's 31), and better [[floating point]] performance,<ref>See Wikipedia article on [[X87#Performance|X87 Performance]]</ref> more than offsetting the difference in raw clock speed. Also, while the Athlon 64 X2 inherited mature [[Multi-core (computing)|multi-core]] control logic from the [[Opteron#Multi-core Opterons|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 (computing)|multi-core]] was superior to that of the Pentium D.<ref name="X2Review1">{{cite web|url=http://reviews.cnet.com/4520-10442_7-6389077-9.html|title=CNET Prizefight: AMD vs. Intel dual-core CPUs|access-date=2006-07-07|date=2005-11-23|last=Brown|first=Rich}}</ref><ref name="X2Review2">{{cite web|url=http://www.tomshardware.com/2005/05/09/amd/|title=AMD's Dual Core Athlon 64 X2 Strikes Hard|access-date=2006-07-07|date=2005-05-09|last=Schmid|first=Patrick}}</ref> As a result of this and other factors, AMD surpassed Intel in desktop PC 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.<ref name="MarketShift1">{{cite web|url=http://news.cnet.com/AMD-surpasses-Intel-in-U.S.-retail-stores/2100-1006_3-5939522.html|title=AMD surpasses Intel in U.S. retail stores|access-date=2009-12-29|date=2005-11-08|last=Kawamoto|first=Dawn}}</ref>

== 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)|Core microarchitecture]] (which was based upon the [[Pentium M]] architecture, which was itself based upon the [[Pentium III]] Tualatin). 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 2×2 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.

==See also==
* [[List of Intel Pentium D processors]]

==References==
{{Reflist}}

==External links==
* [https://web.archive.org/web/20120815070251/http://www.hardcoreware.net/reviews/review-328-1.htm Pentium D 800 and 900 Series Review]

{{s-start}}
{{s-bef|before = [[Pentium 4]]<br>[[Pentium 4 HT]] }}
{{s-ttl|title = Pentium D |years = 2005–2008 }}
{{s-aft|after = [[Intel Core 2]] }}
{{s-end}}

{{Intel processors|netburst}}

[[Category:Computer-related introductions in 2005]]
[[Category:Intel x86 microprocessors]]