Editing PowerPC G4

{{Short description|Apple-branded microprocessor}}
{{POWER, PowerPC, and Power ISA}}
'''PowerPC G4''' is a designation formerly used by [[Apple Inc.|Apple]] to describe a ''fourth generation'' of 32-bit [[PowerPC]] [[microprocessor]]s. Apple has applied this name to various (though closely related) processor models from [[Freescale Semiconductor|Freescale]], a former part of [[Motorola]]. Motorola and Freescale's internal name of this family of processors is '''PowerPC 74xx'''.

[[Macintosh]] computers such as the [[PowerBook G4]] and [[iBook|iBook G4]] laptops and the [[Power Mac G4]] and [[Power Mac G4 Cube]] desktops all took their name from the processor. PowerPC G4 microprocessors were also used in the [[eMac]], first-generation [[Xserve]]s, first-generation [[Mac Mini]]s, and the [[iMac G4]] before the introduction of the [[PowerPC 970]].

Apple completely phased out the G4 series for desktop models after it selected the 64-bit IBM-produced PowerPC 970 processor as the basis for its [[PowerPC G5]] series. The last desktop model that used the G4 was the Mac Mini. The last portable to use the G4 was the [[iBook]] G4, which was replaced by the Intel-based [[MacBook]]. The PowerBook G4 was replaced by the Intel-based [[MacBook Pro]].

The PowerPC G4 microprocessors were also popular in other computer systems, such as the [[AmigaOne]] series of computers and the [[Pegasos]] from [[Genesi]]. Besides desktop computers the PowerPC G4 was popular in embedded environments, like routers, telecom switches, imaging, media processing, avionics and military applications, where one can take full advantage of the [[AltiVec]] technology and its [[Symmetric multiprocessing|SMP]] capabilities.

==PowerPC 7400==<!-- This section is linked from [[List of Macintosh models grouped by CPU type]] -->
The PowerPC 7400 (code-named "Max") debuted in August 1999 and was the first processor to carry the "G4" moniker. The chip operates at speeds ranging from 350 to 500 [[Megahertz|MHz]] and contains 10.5 million transistors, manufactured using Motorola's 0.20 μm HiPerMOS6 process. The [[Die (integrated circuit)|die]] measures 83&nbsp;mm<sup>2</sup> and features [[Copper-based chips|copper interconnects]].

Motorola had promised Apple to deliver parts with speed up to 500&nbsp;MHz, but [[Fabrication (semiconductor)#Device test|yields]] proved too low initially. This forced Apple to take back the advertised 500&nbsp;MHz models of [[Power Mac G4]]. The Power Mac series was downgraded abruptly from 400, 450, and 500&nbsp;MHz processor speeds to 350, 400, and 450&nbsp;MHz while problems with the chip were ironed out. The incident generated a rift in the Apple-Motorola relationship, and reportedly caused Apple to ask IBM for assistance to get the production yields up on the Motorola 7400 series line.<ref>{{Cite web|url=https://www.macworld.com/article/158184/motorola-7.html|title=Motorola and IBM Reveal PowerPC Plans}}</ref> The 500&nbsp;MHz model was reintroduced on February 16, 2000.

=== Design ===
Much of the 7400 design was done by Motorola in close co-operation with [[Apple Inc.|Apple]] and [[IBM]]. IBM, the third member of the [[AIM alliance]], designed the chip together with Motorola in its Somerset design center, but chose not to manufacture it, because it did not see the need back then for the Vector Processing Unit. Ultimately, the G4 architecture design contained a 128-bit vector processing unit labelled [[AltiVec]] by Motorola while Apple marketing referred to it as the "Velocity Engine".

The [[PowerPC 970]] (G5) was the first IBM-manufactured CPU to implement [[AltiVec|VMX/AltiVec]], for which IBM reused the old 7400 design they still had from the design they did with Motorola in Somerset. The [[Xenon (processor)|Xenon]] CPU in the [[Xbox 360]] also features VMX, with added proprietary extensions made especially for Microsoft. [[POWER6]], introduced in 2007, is IBM's first "[[big iron (computing)|big iron]]" CPU to also implement VMX.

With the AltiVec unit, the 7400 microprocessor can do four-way single precision (32-bit) floating point math, or 16-way 8-bit, 8-way 16-bit or four-way 32-bit integer math in a single cycle. Furthermore, the vector processing unit is [[superscalar]], and can do two vector operations at the same time.  Compared to [[Intel]]'s [[x86]] microprocessors at the time, this feature offered a substantial performance boost to applications designed to take advantage of the AltiVec unit. Some examples are Adobe Photoshop which utilises the AltiVec unit for faster rendering of effects and transitions, and Apple's [[iLife]] suite which takes advantage of the unit for importing and converting files on the fly.

Additionally, the 7400 has enhanced support for [[symmetric multiprocessing]] (SMP) thanks to an improved cache coherency protocol ([[MERSI protocol|MERSI]]) and a 64-bit [[floating point unit]] (FPU), derived in part from the [[PowerPC 600#PowerPC 604|604 series]]. The [[PowerPC 600#PowerPC 603|603 series]] had a 32-bit FPU, which took two [[clock cycle]]s to accomplish 64-bit [[floating point]] arithmetic.

The PowerPC G4 family supports two bus technologies, the older [[PowerPC 600#60x bus|60x bus]] which it shares with the [[PowerPC 600]] and [[PowerPC 7xx]] families, and the notably more advanced MPX bus. Devices that utilize the 60x bus can be made compatible with either 6xx or 7xx processors, enabling a wide variety of offerings and a clear and cheap upgrade path while keeping compatibility issues at a minimum. There are primarily two companies manufacturing system controllers for 7xx and 7xxx computers, [[Tundra Semiconductor|Tundra]] with their Tsi1xx controllers and [[Marvell Technology Group|Marvell]] with their Discovery controllers.

==PowerPC 7410==
The PowerPC 7410 "Nitro" is a low-power version of the 7400 but it was manufactured at 180&nbsp;nm instead of 200&nbsp;nm. Like the 7400 it has 10.5 million transistors. It debuted in the [[PowerBook G4]] on 9 January 2001.

The chip added the ability to use all or half of its cache as high-speed, non-cached memory mapped to the processor's physical address space as desired. This feature was used by [[embedded system]]s vendors such as [[Mercury Computer Systems]].

==PowerPC 7450==
[[Image:XPC7450.jpg|thumb|150px|An 800 MHz (Fast) Motorola PowerPC 7450 on a Power Mac G4 CPU module]]
[[Image:PowerPC G4e.png|thumb|right|250px|PowerPC G4e design]]
The PowerPC 7450 "Voyager"/"V'ger" was the only major redesign of the G4 processor. The 33-million transistor chip extended significantly the execution pipeline of 7400 (7 vs. 4 stages minimum) to reach higher clock speeds, improved instruction throughput (3&nbsp;+ branch vs. 2&nbsp;+ branch per cycle) to compensate for higher instruction latency, replaced an external L2 cache (up to 2&nbsp;MB 2-way set associative, 64-bit data path) with an integrated one (256&nbsp;KB 8-way set associative, 256-bit data path), supported an external L3 cache (up to 2&nbsp;MB 8-way set associative, 64-bit data path), and featured many other architectural advancements. The AltiVec unit was improved with the 7450; instead of executing one vector [[permute instruction]] and one vector ALU (simple int, complex int, float) instruction per cycle like 7400/7410, the 7450 and its Motorola/Freescale-followers can execute two arbitrary vector instructions simultaneously (permute, simple int, complex int, float). It was introduced with the 733&nbsp;MHz [[Power Mac G4]] on 9 January 2001. Motorola followed with an interim release, the 7451, codenamed "Apollo 6", just like the 7455. Early [[AmigaOne]] XE computers were shipped with the 7451 processor.

The enhancements to the 745x design gave it the nicknames '''G4e''' or '''G4+''' but these were never official designations.

==PowerPC 7445 and 7455==
[[Image:MotoProto7445.jpg|thumb|190px|A 1.25 GHz (Even faster) Sample 7445 EVT prototype on an iMac G4 DVT model]]

The PowerPC 7455 "Apollo 6" was introduced in January 2002. It came with a wider, 256-bit on-chip cache path, and was fabricated in Motorola's 0.18&nbsp;μm (180&nbsp;nm) HiPerMOS process with copper interconnects and [[Silicon on insulator|SOI]]. It was the first processor in an Apple computer to pass the 1&nbsp;GHz mark.
The 7445 is the same chip without the L3 cache interface.
The 7455 is used in the [[AmigaOne]] XE G4, and the dual 1&nbsp;GHz [[Power Mac G4#Digital Audio/Quicksilver|Power Mac G4 (Quicksilver 2002)]]{{Broken anchor|date=2025-01-14|bot=User:Cewbot/log/20201008/configuration|target_link=Power Mac G4#Digital Audio/Quicksilver|reason= The anchor (Digital Audio/Quicksilver) [[Special:Diff/1092400619|has been deleted]].}}

==PowerPC 7447 and 7457==
The PowerPC 7447 "Apollo 7" is slightly improved from the 7450/55, it has a 512 KB on-chip L2 cache and was manufactured in a [[130 nanometer|130&nbsp;nm]] process with SOI, hence drawing less power. It has 58 million transistors. With the 7447A, which introduced an integrated thermal diode as well as DFS ([[dynamic frequency scaling]]) Freescale was able to reach a slightly higher clock.{{Clarify|date=August 2009}} The 7447B is effectively a 7447A with even higher frequency scaling, with clock rates up to 1.7&nbsp;GHz officially and easily up to 2.4&nbsp;GHz through [[overclocking]].<ref>[https://web.archive.org/web/20151020175158/http://www.freescale.com/files/shared/doc/pcn/PCN11161.htm FREESCALE PRODUCT BULLETIN 11161]</ref><ref>[https://www.nxp.com/docs/en/reliability-and-quality-information/MC7447AQUAL.pdf MC7447A/B/C Microprocessor MOS-13 HiP7SOI 41 - L25S / 42 - L25S / 53 – L25S / 55 – L25S / 58 – L25S Qualification Report]</ref> The 7457 and 7457A have an additional L3 cache interface, supporting up to 4 MB of L3 cache, up from 2 MB supported by the 7455 and 7450. However, its frequency scaling stagnated when Apple chose to use the 7447(s) instead of the 7457(s), despite the 7457 being the L3 cache-enabled successor to the L3 cache-enabled 7455 that Apple used before.

The only companies that offer the 7457 in the form of upgrades for the [[Power Mac G4]], [[iMac G4]], and [[Power Mac G4 Cube]] are Giga Designs, Sonnet Technology, Daystar Technology (they use the 7457 only for iMac G4 upgrades) and PowerLogix. The [[Pegasos]] computer platform from [[Genesi]] also uses 7447 in its Pegasos-II/G4.

The 7457 is often used to repair an AmigaOne XE CPU module;<ref>{{Cite web|url=http://www.intuitionbase.com/printstatic.php?section=en_cpu-repair&char=|title=IntuitionBase - Your Guide To AmigaOS4.x And The AmigaOne|website=www.intuitionbase.com|access-date=2018-07-12|archive-date=2021-06-10|archive-url=https://web.archive.org/web/20210610214905/http://www.intuitionbase.com/printstatic.php?section=en_cpu-repair&char=|url-status=dead}}</ref><ref>{{Cite web|url=https://www.amigans.net/modules/xforum/viewtopic.php?forum=4&topic_id=7503&order=|title=AmigaOne XE, manual cites incorrect vCore?? [Forums - AmigaOS4] - The Amigans website|website=www.amigans.net}}</ref><ref>{{cite press release |author=<!--Staff writer(s); no by-line.--> |url=http://www.acube-systems.biz/index.php?page=news&id=1|title=ACube Systems new corporate website|location=Bassano del Grappa, Italy |publisher=ACube|date=February 24, 2007|access-date=June 12, 2014}}</ref><ref>{{cite web |url=http://www.amiga-news.de/de/news/AN-2007-02-00084-EN.html|title=ACube Systems: Company web page|publisher=Amiga-News.de|date=February 25, 2007|access-date=June 11, 2014}}</ref> some [[AmigaOS]] software with the 7457 installed may mistake the AmigaOne for a Pegasos II computer as there were never any official 7457 boards released by [[Eyetech]].

==PowerPC 7448==

The PowerPC 7448 "Apollo 8" is an evolution of the PowerPC 7447B announced at the first Freescale Technology Forum in June 2005. Improvements were a larger 1&nbsp;MB L2 cache, a faster 200&nbsp;MHz front side bus, and lower power consumption (18&nbsp;W at 1.7&nbsp;GHz). It was fabricated in a 90&nbsp;nm process with copper interconnects and SOI.

PowerPC 7448 users were:

* Daystar for their High-Res Aluminum PowerBook G4 upgrades (Daystar's Low-Res Aluminum PowerBook G4 upgrades used the 7447A, not the 7448)
* NewerTech for their Power Mac G4 upgrades
* PowerLogix for their Power Mac G4 Cube upgrade
* Cisco in NPE-G2 network processor module for their 7200VXR routers <ref>{{Cite web|url=https://www.cisco.com/c/en/us/td/docs/routers/7200/install_and_upgrade/network_process_engine_install_config/npense/4448o6.html|title=Network Processing Engine and Network Services Engine Installation and Configuration - NPE-G2 Overview [Cisco 7200 Series Routers]|website=Cisco}}</ref>
* Cisco 7201 Router <ref>{{Cite web|url=https://www.cisco.com/c/en/us/products/collateral/routers/7201-router/product_data_sheet0900aecd80630b58.html|title=Cisco 7201 Router|website=Cisco}}</ref>
* Extreme Engineering Solutions for their XPedite6244 single board computer <ref>{{Cite web|url=https://www.xes-inc.com/products/end-of-life-sbcs/xpedite6244/|title=XPedite6244 &#124; NXP MPC7448 AMC Module}}</ref>
* Aitech for their C104 CompactPCI single board computer <ref>{{cite web |url=http://www.rugged.com/c104-powerpc%C2%AE-mpc7448-compactpci-sbc |title=C104 PowerPC® MPC7448 CompactPCI SBC {{!}} Aitech Rugged COTS Solutions |website=www.rugged.com |url-status=dead |archive-url=https://web.archive.org/web/20160731054603/http://www.rugged.com/c104-powerpc%C2%AE-mpc7448-compactpci-sbc |archive-date=2016-07-31}} </ref>
* [[Vertiv|Emerson Network Power]] for their PmPPC7448 PMC module <ref>{{Cite web| title=PowerPC based Processor PMC | url=http://static6.arrow.com/aropdfconversion/ad4aa5d5f0e38c4028118cabe7ce2d17a41e7530/pmppc7448%20ds.pdf | archive-url=https://web.archive.org/web/20170906040503/http://static6.arrow.com/aropdfconversion/ad4aa5d5f0e38c4028118cabe7ce2d17a41e7530/pmppc7448%20ds.pdf | archive-date=2017-09-06}}</ref>

== e600 ==
{{Main|PowerPC e600}}

In 2004, Freescale renamed the G4 core to '''e600''' and changed its focus from general CPUs to high-end embedded [[system-on-a-chip|SoC]] devices, and introduced a new naming scheme, MPC86xx. The 7448 was to be the last pure G4 and it formed the base of the new e600 core with a seven-stage, three-issue pipeline, and a powerful [[branch predictor|branch prediction unit]] which handles up to sixteen instructions out-of-order. It has an enhanced AltiVec unit capable of limited [[out-of-order execution]] and a 1&nbsp;MB L2 cache.

== Device list ==
''This list is a complete list of known G4 based designs (excluding newer core e600 designs). The pictures are illustrations and not to scale.''

{| class="wikitable"
|-
! Name !! Manufacturer !! Image !! Fab !! Transistors !! Die size !! Cores !! Clock !! L2 cache !! L3 cache 
!Consumption!! Package 
!Multiplier!! Introduced
|-
| MPC7400
| Motorola
| [[File:MPC7400.jpg|100px]]
| 0.20 μm
| 10.5 M
| 83&nbsp;mm<sup>2</sup>
| 1
| 350–500&nbsp;MHz
| 512–2048 kB<br /> off die
| n/a
|4.6W @ 350MHz
5.3W @ 400MHz
| 360 pin CBGA
|2-8, 9
| 1999
|-
| 06K5319<br />10K8298
| IBM
| [[File:IBM-06K5319.jpg|100px]]
| 0.18 μm
| 10.5 M
| 
| 1
| 400–500&nbsp;MHz
| 512–2048 kB<br /> off die
| n/a
|
| 360 pin CBGA
|
| 2000
|-
| MPC7410
| Motorola<br />Freescale
| [[File:MPC7410-Freescale.jpg|100px]]
| 0.18 μm
| 10.5 M
| 52&nbsp;mm<sup>2</sup>
| 1
| 400–550&nbsp;MHz
| 512–2048 kB<br /> off die
| n/a
|4.2W @ 400MHz
5.3W @ 500MHz
| 360 pin CBGA<br />360 pin CLGA
|2-8, 9
| 2001
|-
| MPC7450<br />MPC7451
| Motorola
| [[File:MPC7450.jpg|100px]]
| 0.18 μm
| 33 M
| 106&nbsp;mm<sup>2</sup>
| 1
| 500–867&nbsp;MHz
| 256 kB
| 0–2 MB<br />off die
|11.6W @ 533MHz
14.5W @ 667MHz
| 483 pin CBGA
|0.5
2-8

9-16
| 2001
|-
| MPC7440<br />MPC7441
| Motorola
| [[File:MPC7440.jpg|100px]]
| 0.18 μm
| 33 M
| 106&nbsp;mm<sup>2</sup>
| 1
| 500–800&nbsp;MHz
| 256 kB
| n/a
|11.6W @ 533MHz
14.5W @ 667MHz
| 360 pin CBGA
|0.5
2-8

9-16
| 2001
|-
| MPC7455
| Motorola
| [[File:MPC7455.jpg|100px]]
| 0.18 μm SOI
| 33 M
| 106&nbsp;mm<sup>2</sup>
| 1
| 600–1420&nbsp;MHz
| 256 kB
| 0–2 MB<br />off die
|13W @ 600MHz
21.3W @ 1GHz
| 483 pin CBGA
|0.5
2-8

9-16
| 2002
|-
| MPC7445
| Motorola
| [[File:MPC7445.jpg|100px]]
| 0.18 μm SOI
| 33 M
| 106&nbsp;mm<sup>2</sup>
| 1
| 600–1420&nbsp;MHz
| 256 kB
| n/a
|13W @ 600MHz
21.3W @ 1GHz
| 360 pin CBGA
|0.5
2-8

9-16
| 2002
|-
| MPC7457
| Motorola<br />Freescale
| [[File:MPC7457.jpg|100px]]
| 0.13 μm SOI
| 58 M
| 98.3&nbsp;mm<sup>2</sup>
| 1
| 867–1267&nbsp;MHz
| 512 kB
| 0–4 MB<br />off die
|14.8W @ 867MHz
18.3W @ 1267MHz
| 483 pin CBGA
|2-28
| 2003
|-
| MPC7447<br />MPC7447/A
| Motorola<br />Freescale
| [[File:MPC7447A.jpg|100px]]
| 0.13 μm SOI
| 48.6 M
| 83.9&nbsp;mm<sup>2</sup>
| 1
| 600–1420&nbsp;MHz<br />600–1600&nbsp;MHz
| 512 kB
| n/a
|(7447A)
16W @ 1GHz

21W @ 1.42GHz
| 360 pin CBGA<br />360 pin CLGA
|2-28
| 2003<br />2004
|-
| MPC7448
| Freescale
| [[File:MPC7448.jpg|100px]]
| 90&nbsp;nm SOI
| 90 M
| 58.44&nbsp;mm<sup>2</sup>
| 1
| 1000–1700&nbsp;MHz
| 1024 kB
| n/a
|15W @ 1GHz
21W @ 1.7GHz
| 360 pin CBGA<br />360 pin CLGA
|2-28
| 2005
|}

== See also ==
* [[List of Macintosh models grouped by CPU type]]

== References ==
{{Reflist}}
* [[Keith Diefendorff|Diefendorff, Keith]] (25 October 1999). "PowerPC G4 Gains Velocity". ''[[Microprocessor Report]]''. pp.&nbsp;10&ndash;15.
* Gwennap, Linley (16 November 1998). "G4 Is First PowerPC With AltiVec". ''[[Microprocessor Report]]''.
* Halfhill, Tom R. (5 July 2005). "PowerPC Ain't Dead Yet". ''[[Microprocessor Report]]''. pp.&nbsp;13&ndash;15.

{{Motorola processors}}

{{DEFAULTSORT:Powerpc G4}}

[[Category:PowerPC microprocessors|G4]]
[[Category:Motorola microprocessors]]
[[Category:Superscalar microprocessors]]
[[Category:32-bit microprocessors]]