Editing Socket 478

{{Short description|Processor socket made by Intel}}
{{CPU socket|
name = Socket 478 |
image = [[File:Socket PGA478B.jpg|300px]] |
formfactors = [[Flip-chip pin grid array]] (FC-PGA2 or FC-PGA4) |
contacts = 478 (not to be confused with the newer [[Socket P]] or the similar [[Socket 479]])|
type = PGA-ZIF |
protocol = AGTL+ |
fsb = 400 MT/s<br>533 MT/s<br>800 MT/s |
voltage =1.25 V - 1.525 V  |
dimensions = 35 mm x 35 mm<ref>{{webarchive |url=https://web.archive.org/web/20060409050735/http://www.intel.com:80/design/pentium4/datashts/24988703.pdf |date=April 09, 2006 |title=Intel Pentium 4 Datasheet }}</ref> |
processors = [[Pentium 4]] (1.4–3.4 GHz)<br>[[Celeron]] (1.7–2.8 GHz)<br> [[Celeron#Prescott-256|Celeron D]] (2.13–3.2 GHz)<br>[[Pentium_4#Gallatin (Extreme_Edition)|Pentium 4 Extreme Edition]] (3.2–3.4 GHz)
| predecessor = [[Socket 423]]
| successor   = [[LGA 775]]
|release-date=2001|designed-by=Intel}}

[[File:Pentium 4 - SL5TK - pin side-3057.jpg|thumb|right|250px|[[Pentium 4]] [[Pentium_4#Willamette|Willamette]] with Socket 478 (2001), pin side]]
'''Socket 478''', also known as '''mPGA478''' or '''mPGA478B''', is a 478-contact [[CPU socket]] used for [[Intel]]'s [[Pentium 4]] and [[Celeron]] series [[Central processing unit|CPUs]]. 

Socket 478 was launched in August 2001 in advance of the Northwood core to compete with [[AMD]]'s 462-pin [[Socket A]] and their [[Athlon XP]] processors.  Socket 478 was intended to be the replacement for [[Socket 423]], a Willamette-based processor socket which was on the market for only a short time. 

This was the last Intel desktop socket to use a pin grid array ([[Pin grid array|PGA]]) interface. All later Intel desktop sockets use a land grid array ([[Land grid array|LGA]]) interface.

Socket 478 was phased out with the launch of [[LGA 775]] in 2004.

==Technical specifications==
Socket 478 was used for all [[Pentium_4#Northwood|Northwood Pentium 4]] and [[Celeron]] processors. It supported the first [[Pentium_4#Prescott|Prescott Pentium 4]] processors and all [[Pentium_4#Willamette|Willamette]] Celerons, along with several of the Willamette-series Pentium 4s. Socket 478 also supported the newer Prescott-based Celeron D processors (which were also one of the  last CPUs made for the socket), and early Pentium 4 Extreme Edition processors with 2&nbsp;MB of L3 [[CPU cache]].

While Intel's mobile CPUs are available in 478-pin packages, they in fact only operate in a range of slightly differing sockets such as [[Socket 479]], [[Socket M]], and [[Socket P]], all of which are electrically incompatible with each other including Socket 478.<ref>{{Cite web|url=https://www.cpu-world.com/Sockets/Socket%20479%20(mPGA479M).html|title=Socket 479 / Socket mPGA479M|website=www.cpu-world.com|access-date=February 3, 2025}}</ref>

Socket 478 is used in combination with [[DDR SDRAM]], as well as SDR SDRAM, [[RDRAM]] and [[DDR2 SDRAM]].

== Heatsink ==
The 4 holes for fastening the heatsink to the motherboard are placed in a rectangle with lateral lengths of 60 mm and 75 mm.

==Mechanical load limits==
All sockets (Pentium 4 and Celeron) have the following mechanical maximum load limits which should not be exceeded during heatsink assembly, shipping conditions, or standard use. Load above those limits may crack the processor die and make it unusable. The limits are included in the table below.
{| class="wikitable" style="font-size: 95%; text-align: center;"
|-
! rowspan=1 style="width:12em" | Location
! rowspan=1 | Dynamic
! rowspan=1 | Static
! rowspan=1 | Transient
|-
| IHS Surface
| 890 [[newton (unit)|N]] (200 [[Pound-force|lb<sub>f</sub>]])
| 445 [[newton (unit)|N]] (100 [[Pound-force|lb<sub>f</sub>]])
| 667 [[newton (unit)|N]] (150 [[Pound-force|lb<sub>f</sub>]])
|}

==Chipsets==
=== Intel ===
{{further|List of Intel chipsets#Pentium 4 chipsets}}

==See also==
* [[List of Intel microprocessors]]

==References==
<references />

==External links==
*{{webarchive |url=https://web.archive.org/web/20060518013417/http://www.intel.com/design/pentium4/guides/24989002.pdf |date=May 18, 2006 |title=Socket information }}

{{intelsock}}

[[Category:Intel CPU sockets]]