Xeon (; ) is a brand of x86 microprocessors designed, manufactured, and marketed by Intel, targeted at the non-consumer workstation, server, and embedded markets. It was introduced on June 29, 1998. Xeon processors are based on the same architecture as regular desktop-grade CPUs, but have advanced features such as support for error correction code (ECC) memory, higher core counts, more PCI Express (PCIe) lanes, support for larger amounts of RAM, larger cache memory and extra provision for enterprise-grade reliability, availability and serviceability (RAS) features responsible for handling hardware exceptions through the Machine Check Architecture (MCA). They are often capable of safely continuing execution where a normal processor cannot due to these extra RAS features, depending on the type and severity of the machine-check exception (MCE). Some also support multi-socket systems with two, four, or eight sockets through use of the Ultra Path Interconnect (UPI) bus, which replaced the older QuickPath Interconnect (QPI) bus.
Branding The Xeon brand has been maintained over several generations of IA-32 and x86-64 processors. The P6-based models added the Xeon moniker to the end of the name of their corresponding desktop processor, but all models since 2001 used the name Xeon on its own. The Xeon CPUs generally have more cache and cores than their desktop counterparts in addition to multiprocessing capabilities.
Xeon Scalable The Xeon Scalable brand for high-performance server was introduced in May 2017 with the Skylake-based Xeon Platinum 8100 series. Xeon Scalable processors range from dual socket to 8 socket support. Within the Xeon Scalable brand, there exists the hierarchy of Xeon Bronze, Silver, Gold and Platinum.
In April 2024, Intel announced at its Vision event that the Xeon Scalable brand would be retired, beginning with 6th generation Xeon processors codenamed Sierra Forest and Granite Rapids that will now be referred to as "Xeon 6" processors. This change brings greater emphasis on processor generation numbers.
Xeon 6 With the launch of Intel's Sierra Forest line of processors, branding for mainstream server processors switched to Xeon #, with the # being the generation of the processor, such as Xeon 6 for the 6th generation of Xeon processors, this naming convention also carries over to the Granite Rapids line of server CPUs.
Xeon 6 is split into two product lines, the E series and P series, which, respectively, are all E core and all P core designs. For example, the Xeon 6 6700E line is an all E core based (Sierra Forest) line of processors.
Xeon D
Xeon D is targeted towards microserver and edge computing markets with lower power consumption and integrated I/O blocks such as network interface controllers. This allows Xeon D processors to function as SoCs that do not require a separate southbridge PCH. It was announced in 2014 and the first Xeon D processors were released in March 2015. Xeon D processors come in an soldered BGA package rather than in a socketable form factor. Xeon D was introduced to compete with emerging ARM hyperscale server solutions that offered greater multi-threaded performance and power efficiency.
Early 2025, the Xeon 6 SoC line was announced as the 'next gen' for at least a part of the Xeon D lineup.
Xeon W
Xeon W branding is used for Xeon workstation processors. It was first introduced in August 2017 with the release of the Skylake-based Xeon W-2100 series workstation processors. With Sapphire Rapids-WS workstation processors that launched in March 2023, Intel introduced tiers within Xeon W. Xeon w3, w5, w7 and w9 was designed to emulate the Core i3, i5, i7 and i9 branding that Intel had been using for its desktop processors.
Overview Some shortcomings that make Xeon processors unsuitable for most consumer-grade desktop PCs include lower clock rates at the same price point (since servers run more tasks in parallel than desktops, core counts are more important than clock rates), and, usually, the lack of an integrated graphics processing unit (GPU). Processor models prior to Sapphire Rapids-WS lack support for overclocking (with the exception of Xeon W-3175X). Despite such disadvantages, Xeon processors have always had popularity among some desktop users (video editors and other power users), mainly due to higher core count potential, and higher performance to price ratio vs. the Core i7 in terms of total computing power of all cores. Since most Intel Xeon CPUs lack an integrated GPU, systems built with those processors require a discrete graphics card or a separate GPU if computer monitor output is desired.
Intel Xeon is a distinct product line from the similarly named Intel Xeon Phi. The first-generation Xeon Phi is a completely different type of device more comparable to a graphics card; it is designed for a PCI Express slot and is meant to be used as a multi-core coprocessor, like the Nvidia Tesla. In the second generation, Xeon Phi evolved into a main processor more similar to the Xeon. It conforms to the same socket as a Xeon processor and is x86-compatible; however, as compared to Xeon, the design point of the Xeon Phi emphasizes more cores with higher memory bandwidth.
+ Intel Xeon processor family: Server 1 or 2 SocketsUP/DP/3000/5000/E3/E5-1xxx and 2xxx/E7-2xxx/D/E/W seriesBronze/Silver/Gold (non H)/Platinum (non H)/Max 4 or 8 SocketsMP/7000/E5-4xxx/E7-4xxx and 8xxx seriesGold (H)/Platinum (H) Node Code named # ofCores Releasedate Code named # ofCores Releasedate 250 nm Drake 1 Jun 1998 Tanner 1 Mar 1999 180 nm Cascades (256 KB L2 cache) 1 Oct 1999 Cascades (700 and 900 MHz models only) 1 May 2000 Foster 1 May 2001 Foster MP 1 Mar 2002 130 nm Prestonia 1 Feb 2002 Gallatin DP 1 Jul 2003 Gallatin 1 Nov 2002 90 nm Nocona 1 Jun 2004 Cranford 1 Mar 2005 Potomac 1 Mar 2005 Irwindale 1 Feb 2005 Paxville DP 2 Oct 2005 Paxville 2 Nov 2005 65 nm Dempsey 2 May 2006 Tulsa 2 Aug 2006 Sossaman 2 Mar 2006 Woodcrest 2 Jun 2006 Conroe 2 Oct 2006 Clovertown 4 Nov 2006 Tigerton/Tigerton QC 2/4 Sep 2007 Allendale 2 Jan 2007 Kentsfield 4 Jan 2007 45 nm Wolfdale DP 2 Nov 2007 Harpertown 4 Nov 2007 Dunnington QC/Dunnington 4/6 Sep 2008 Wolfdale 2 Feb 2008 Yorkfield 4 Mar 2008 Bloomfield (W35xx) 4 Mar 2009 Gainestown (55xx) 2/4 Mar 2009 Lynnfield (34xx) 4 Sep 2009 Beckton (65xx) 4/6/8 Mar 2010 Beckton (75xx) 4-8 Mar 2010 32 nm Westmere-EP (56xx) 2-6 Mar 2010 Gulftown (W36xx) 6 Mar 2010 Clarkdale (L34xx) 2 Mar 2010 Westmere-EX (E7-2xxx) 6-10 Apr 2011 Westmere-EX (E7-4xxx/8xxx) 6-10 Apr 2011 Sandy Bridge-DT/EN/EP 2-8 Mar 2012 Sandy Bridge-EP (E5-46xx) 4-8 May 2012 22 nm Ivy Bridge (E3/E5-1xxx/E5-2xxx v2) 2-12 Sep 2013 Ivy Bridge-EP (E5-46xx v2) 4-12 Mar 2014 Ivy Bridge-EX (E7-28xx v2) 12/15 Feb 2014 Ivy Bridge-EX (E7-48xx/88xx v2) 6-12/15 Feb 2014 Haswell (E3/E5-1xxx/E5-2xxx v3) 2-18 Sep 2014 Haswell-EP (E5-46xx v3) 6-18 Jun 2015 Haswell-EX (E7-48xx/88xx v3) 4-18 May 2015 14 nm Broadwell (E3/E5-1xxx/E5-2xxx v4) 4-22 Jun 2015 Broadwell-EX (E7-48xx/88xx v4) 4-24 Jun 2016 Skylake-S/H (E3-1xxx v5) 4 Oct 2015 Kaby Lake-S/H (E3-1xxx v6) 4 Mar 2017 Skylake-W/SP (Bronze and Silver) 4-28 Jun 2017 Skylake-SP (Gold and Platinum) 4-28 Jul 2017 4-28 Apr 2019 4-28 Apr 2019 Cooper Lake-SP 8-28 Jun 2020 10 nm Ice Lake-SP/W 8-40 Apr 2021 Ice Lake-D 2-20 Feb 2022 7 nm Sapphire Rapids-SP/WS/HBM 6-56 Jan 2023 Sapphire Rapids-SP 8-60 Jan 2023 Emerald Rapids-SP 8-64 Dec 2023 3 nm Sierra Forest-SP/AP 64-288 Jun 2024 Granite Rapids-SP/AP/HBM 8-128 Sep 2024 Granite Rapids-SP 8-86 Sep 2024 Granite Rapids-D 12-72 Feb 2025 Granite Rapids-WS 12-86 Feb 2026 2 nm Clearwater Forest-AP 288 Jun 2026 List of Intel Xeon processors
P6-based Xeon
Pentium II Xeon
The first Xeon-branded processor was the Pentium II Xeon (code-named "Drake"). It was released in 1998, replacing the Pentium Pro in Intel's high-end server lineup. The Pentium II Xeon was a "Deschutes" Pentium II (and shared the same product code: 80523) with a full-speed 512 kB (1 kB = 1024 B), 1 MB (1 MB = 1024 kB = 10242 B), or 2 MB L2 cache. The L2 cache was implemented with custom 512 kB SRAMs developed by Intel. The number of SRAMs depended on the amount of cache. A 512 kB configuration required one SRAM, a 1 MB configuration: two SRAMs, and a 2 MB configuration: four SRAMs on both sides of the PCB. Each SRAM was a 12.90 mm by 17.23 mm (222.21 mm) die fabricated in a 0.35 μm four-layer metal CMOS process and packaged in a cavity-down wire-bonded land grid array (LGA). The additional cache required a larger module and thus the Pentium II Xeon used a larger slot, Slot 2. It was supported by the i440GX dual-processor workstation chipset and the i450NX quad- or octo-processor server chipset.
Pentium III Xeon
In 1999, the Pentium II Xeon was replaced by the Pentium III Xeon. Reflecting the incremental changes from the Pentium II "Deschutes" core to the Pentium III "Katmai" core, the first Pentium III Xeon, named "Tanner", was just like its predecessor except for the addition of Streaming SIMD Extensions (SSE) and a few cache controller improvements. The product codes for Tanner mirrored that of Katmai; 80525.
The second version, named "Cascades", was based on the Pentium III "Coppermine" core. The "Cascades" Xeon used a 133 MT/s front side bus and relatively small 256 kB on-die L2 cache resulting in almost the same capabilities as the Slot 1 Coppermine processors, which were capable of dual-processor operation but not quad-processor or octa-processor operation.
To improve this situation, Intel released another version, officially also named "Cascades", but often referred to as "Cascades 2 MB". That came in two variants: with 1 MB or 2 MB of L2 cache. Its bus speed was fixed at 100 MT/s, though in practice the cache was able to offset this. The product code for Cascades mirrored that of Coppermine; 80526.
NetBurst-based Xeon Xeon (DP) and Xeon MP (32-bit) Foster
In mid-2001, the Xeon brand was introduced ("Pentium" was dropped from the name). The initial variant that used the new NetBurst microarchitecture, "Foster", was slightly different from the desktop Pentium 4 ("Willamette"). It was a decent chip for workstations, but for server applications it was almost always outperformed by the older Cascades cores with a 2 MB L2 cache and AMD's Athlon MP. Combined with the need to use expensive Rambus Dynamic RAM, the Foster's sales were somewhat unimpressive.
At most two Foster processors could be accommodated in a symmetric multiprocessing (SMP) system built with a mainstream chipset, so a second version (Foster MP) was introduced with 512 KB or 1 MB L3 cache and the Jackson Hyper-Threading capacity. This improved performance slightly, but not enough to lift it out of third place. It was also priced much higher than the dual-processor (DP) versions. The Foster shared the 80528 product code with Willamette.
Prestonia
In 2002, Intel released a 130 nm version of Xeon branded CPU, codenamed "Prestonia". It supported Intel's new Hyper-Threading technology and had a 512 kB L2 cache. This was based on the "Northwood" Pentium 4 core. A new server chipset, E7500 (which allowed the use of dual-channel DDR SDRAM), was released to support this processor in servers, and soon the bus speed was boosted to 533 MT/s (accompanied by a new socket and two new chipsets: the E7501 for servers and the E7505 for workstations). The Prestonia performed much better than its predecessor and noticeably better than Athlon MP. The support of new features in the E75xx series also gave it a key advantage over the Pentium III Xeon and Athlon MP branded CPUs (both stuck with rather old chipsets), and it quickly became the top-selling server/workstation processor.
Gallatin