Ryzen

Ryzen ( ) is a brand of x86-64 microprocessors designed and marketed by Advanced Micro Devices (AMD) for desktop, mobile, server, and embedded platforms based on the Zen microarchitecture. It consists of central processing units (CPUs) marketed for mainstream, enthusiast, server, and workstation segments and accelerated processing units (APUs) marketed for mainstream and entry-level segments and embedded systems applications.
AMD officially announced a new series of processors, named "Ryzen", during its New Horizon summit on December 13, 2016 and introduced Ryzen 1000 series processors in February 2017, featuring up to 8 cores and 16 threads, which launched on March 2, 2017. The second generation of Ryzen processors, the Ryzen 2000 series, features the Zen+ microarchitecture, an incremental improvement built on a 12nm process technology, was released in April 2018 and featured a marginal performance increase over Ryzen 1000 processors that first released in 2017. The third generation of Ryzen processors launched on July 7, 2019 and based on AMD's Zen 2 architecture, features more significant design improvements and a further shrink to Taiwan Semiconductor Manufacturing Company's (TSMC) 7 nm process. On June 16, 2020, AMD announced new Ryzen 3000 series XT processors with 4% higher boost clocks versus non XT processors. On October 8, 2020, AMD announced the highly anticipated Zen 3 architecture for their Ryzen 5000 series processors, featuring a 19% instructions per cycle (IPC) improvement over Zen 2, while being built on the same 7nm TSMC node.
A majority of AMD's consumer Ryzen products use the Socket AM4 platform. In August 2017, AMD launched their Ryzen Threadripper line aimed at the enthusiast workstation market. AMD Ryzen Threadripper uses the larger TR4 and sTRX4 sockets, which support additional memory channels and PCI Express lanes.
In December 2019, AMD started producing first generation Ryzen products built using the second generation Zen+ architecture. The most notable example is Ryzen 5 1600, with newest batches, having "AF" identifier instead of its usual "AE", being essentially a rebadged Ryzen 5 2600 with the same specifications as the original Ryzen 5 1600.
History.
Ryzen is especially significant for AMD since it was a completely new, "from scratch" design and marked the corporation's return to the high-end CPU market after many years of near-total absence. This is because AMD's primary competitor Intel had largely dominated this market segment starting from the 2006 release of their Core microarchitecture (marketed as "Core 2"), after abandoning the Pentium 4's extremely uncompetitive (with AMD's Athlon XP and Athlon 64) Netburst microarchitecture for an upgraded version of the prior Pentium 3 (which notably continues to underpin Intel's CPU designs to this very day). Intel's market dominance over AMD would only continue to increase as simultaneously with the above launch was the successful roll out of their now famous "tick-tock" CPU release strategy, which alternated between a new microarchitecture and a new fabrication node each and every year. Eventually becoming a product release cadence that Intel would manage to stick to for almost an entire decade. 
Also of note is the release of AMD's Bulldozer microarchitecture in 2011, which despite being a clean sheet CPU design like Zen, had been optimized for parallel computing above all else, which was then still very much in its infancy (which led to starkly inferior real-world performance in any workload that wasn't highly threaded) and thus ended up uncompetitive in basically every area outside of raw multithreading and its use in low power APUs with integrated Radeon graphics. Despite a die shrink and several revisions of the Bulldozer architecture, performance and power efficiency failed to catch up with Intel's competing products. Cumulatively, all of this practically forced AMD to abandon the entire high-end CPU market (including desktop, laptops, and server/enterprise) until Ryzen's release in spring 2017.
Ryzen is the consumer-level implementation of the newer Zen microarchitecture, a complete redesign that marked the return of AMD to the high-end CPU market, offering a product stack able to compete with Intel at every level. Having more processing cores, Ryzen processors offer greater multi-threaded performance at the same price point relative to Intel's Core processors. The Zen architecture delivers more than 52% improvement in instructions per cycle (clock) over the prior-generation Bulldozer AMD core, without raising power use. The changes to instruction set also makes it binary-compatible with Intel's Broadwell, smoothing the transition for users.
Threadripper, which is geared for high end desktops (HEDT), wasn't developed as part of a business plan or a specific roadmap; instead, a small enthusiast team inside AMD saw an opportunity that something could be developed between the Ryzen and Epyc CPU roadmaps that would put the crown of performance on AMD. After some progress was made in their spare time, the project was greenlit and put in an official roadmap by 2016.
Since the release of Ryzen, AMD's CPU market share has increased while Intel appears to have stagnated.
Product lineup.
Ryzen 2000.
CPUs.
The first Ryzen 2000 CPUs, based on the 12 nm Zen+ microarchitecture, were announced for preorder on April 13, 2018 and launched six days later.
Zen+ based Ryzen CPUs are based on Pinnacle Ridge architecture, while Threadripper CPUs are based on the Colfax microarchitecture. The first of the 2000 series of Ryzen Threadripper products, introducing Precision Boost Overdrive technology, followed in August. The Ryzen 7 2700X was bundled with the new Wraith Prism cooler.
APUs.
Desktop.
In January 2018, AMD announced the first two Ryzen desktop APUs with integrated Radeon Vega graphics under the Raven Ridge codename. These were based on first generation Zen architecture. The Ryzen 3 2200G and the Ryzen 5 2400G were released in February.
Mobile.
In May 2017, AMD demonstrated a Ryzen mobile APU with four Zen CPU cores and Radeon Vega-based GPU. The first Ryzen mobile APUs, codenamed Raven Ridge, were officially released in October 2017.
Embedded.
Great Horned Owl.
In February 2018, AMD announced the V1000 series of embedded Zen+ Vega APUs, based on the Great Horned Owl architecture, with four SKUs.
Banded Kestrel.
In April 2019, AMD announced another line of embedded Zen+Vega APUs, namely the Ryzen Embedded R1000 series with two SKUs.
Ryzen 3000.
CPUs.
On May 27, 2019, at Computex in Taipei, AMD launched its third generation Ryzen processors which use AMD's Zen 2 architecture. For this generation's microarchitectures, Ryzen uses "Matisse", while Threadripper uses "Castle Peak". The chiplet design separates the CPU cores, fabricated on TSMC's 7FF process, and the I/O, fabricated on GlobalFoundries' 12 nm process, and connects them via Infinity Fabric. The Ryzen 3000 series uses the AM4 socket similar to earlier models and is the first CPU to offer PCI Express 4.0 (PCIe) connectivity. The new architecture offers a 15% instruction-per-clock (IPC) uplift and a reduction in energy usage. Other improvements include a doubling of the L3 cache size, a re-optimized L1 instruction cache, a larger micro-operations cache, double the floating point performance, improved branch prediction, and better instruction pre-fetching. The 6-, 8- and 12-core CPUs became generally available on July 7, 2019, and 24-core processors were launched in November.
The Ryzen Threadripper 3990X, part of Castle Peak generation of CPUs, has currently the world's largest number of both cores and threads available in consumer-oriented CPUs - 64 and 128, respectively. The competing Intel Core i9-10980XE processor has only 18 cores and 36 threads. Another competitor, the workstation-oriented Intel Xeon W-3275 and W-3275M, has 28 cores, 56 threads, and cost more when launched.
The 4-, 6- and 8-core processors have one core chiplet. The 12- and 16-core processors have two core chiplets. In all cases the I/O die is the same.
The Threadripper 24- and 32-core processors have four core chiplets. The 64-core processor has eight core chiplets. All Threadripper processors use the same I/O die.
APUs.
Both mobile and desktop APUs are based on the Picasso microarchitecture, a 12 nm refresh of Raven Ridge, offering a modest increase in clock speeds (up to an additional 300 MHz maximum boost), Precision Boost 2, an up to 3% increase in IPC from the move to the Zen+ core with its reduced cache and memory latencies, and newly added solder thermal interface material for the desktop parts.
Mobile.
In 2019, AMD first released the Ryzen 3000 APUs, consisting only of quad core parts. Then in January 2020, they announced value dual core mobile parts, codenamed Dalí, including the Ryzen 3 3250U.
Ryzen 4000.
APUs.
The Ryzen 4000 APUs are based on Renoir, a refresh of the Zen 2 Matisse CPU cores, coupled with Radeon Vega GPU cores. They were released only to OEM manufacturers in mid-2020. Unlike Matisse, Renoir does not support PCIe 4.0. 
Ryzen Pro 4x50G APUs are the same as 4x00G APUs, except they are bundled a Wraith Stealth cooler and are not OEM-only. It is possible this is a listing mistake, since 4x50G CPUs are unavailable on retail (as of Oct. 2020) and PRO SKUs are usually the OEM only parts.
Mobile.
Zen 2 APUs, based on the 7 nm Renoir microarchitecture, commercialized as Ryzen 4000.
Embedded.
Grey Hawk.
In November 2020, AMD announced the V2000 series of embedded Zen 2 Vega APUs.
Ryzen 5000.
CPUs.
The desktop Ryzen 5000 series, based on the Zen 3 microarchitecture, was announced on October 8, 2020. They use the same 7 nm manufacturing process, which has matured slightly, as usual. Mainstream Ryzen 5000 CPU cores are codenamed Vermeer. Enthusiast/workstation Threadripper 5000 CPU cores are codenamed Genesis.
APUs.
In contrast to their CPU counterparts, the APUs consist of single dies with integrated graphics and smaller caches. The APUs, codenamed Cezanne, forgo PCIe 4.0 support to keep power consumption low. 
Mobile.
Unevenly numbered models like the 5300U, 5500U and 5700U are Zen 2 based (codename Lucienne), while 5400U, 5600U and 5800U are Zen 3 based (codename Cezanne). HX models are unlocked, allowing them to be overclocked like Intel Core i9-xxxxxHK processors. SMT is now standard across the lineup unlike the 4000-series Ryzen Mobile.
Initial reception.
The first Ryzen 7 (1700, 1700X, and 1800X) processors debuted in early March 2017 and were generally well received by hardware reviewers. Ryzen was the first brand new architecture from AMD in five years, and without very much initial fine-tuning or optimization, it ran generally well for reviewers. Initial Ryzen chips ran well with software and games already on the market, performing exceptionally well in workstation scenarios, and well in most gaming scenarios. Compared to Piledriver-powered FX chips, Zen-powered Ryzen chips ran cooler, much faster, and used less power. IPC uplift was eventually gauged to be 52% higher than Excavator, which was two full generations ahead of the architecture still being used in AMD's FX-series desktop predecessors like the FX-8350 and FX-8370. Though Zen fell short of Intel's Kaby Lake in terms of IPC, and therefore single-threaded throughput, it compensated by offering more cores to applications that can use them. Power use and heat were found to be competitive with Intel, and the included Wraith coolers were generally competitive with higher-priced aftermarket units.
Ryzen 1800X's multi-threaded performance, in some cases while using Blender or other open-source software, was around four times the performance of the FX-8370, or nearly double that of the i7 7700K. One reviewer found that Ryzen chips would usually outperform competing Intel i7 processors for a fraction of the price when all eight cores are used.
However, one complaint among a subset of reviewers was that Ryzen processors lagged their Intel counterparts when running older games, or some newer games at mainstream resolutions such as 720p or 1080p. AMD acknowledged the gaming performance deficit at low resolutions during a Reddit "Ask Me Anything" thread, where it explained that updates and patches were being developed. Subsequent updates to "Ashes of the Singularity: Escalation" and "Rise of the Tomb Raider" increased frame rates by 17 to 31% on Ryzen systems. Developer id Software announced in April 2017 it would optimize its future games to make use of the greater parallelism available on Ryzen CPUs.
It has been suggested that low threaded applications often result in Ryzen processors being underused, yielding lower than expected benchmark scores, because Zen relies on its core count to make up for its lower IPC rating than that of Kaby Lake. However, AMD and others have argued thread scheduling is not the fundamental issue to Windows 10 performance. Early AM4 motherboards were also hindered by BIOS bugs and poor DDR4 memory support.
Operating system support.
Windows.
AMD verified that computers with Ryzen CPUs can boot Windows 7 and Windows 8 but on newer hardware, including AMD Ryzen and Intel Kaby Lake and later, Microsoft only officially supports the use of Windows 10. Windows Update blocks updates from being installed on newer systems running older versions of Windows, though that restriction can be circumvented with an unofficial patch.
Although AMD initially announced that Ryzen chipset drivers would not be provided for Windows 7, its chipset driver packages do in fact list and include them.
Linux.
Full support for Ryzen processors' performance features in Linux requires kernel version 4.10 or newer.
Known issues.
Spectre.
Like nearly all modern high performance microprocessors, Ryzen was susceptible to the "Spectre" vulnerabilities. The vulnerabilities can be mitigated without hardware changes via microcode updates and operating system workarounds, but the mitigations incur a performance penalty. AMD Ryzen and Epyc suffer up to 9% penalty from the mitigations, depending on workload, comparing favorably with a penalty of in some cases more than 50% for Intel Core and Xeon processors, in part as a result of the AMD processors not requiring mitigation against the related Meltdown vulnerability.
Launched in 2019, Zen 2 includes hardware mitigations against the Spectre V4 speculative store bypass vulnerability.
Segmentation fault.
Some early shipments of Ryzen 1000 series processors produced segmentation faults on some workloads on Linux, especially while compiling code with GNU Compiler Collection (GCC). AMD offered to replace the affected processors with newer ones that are unaffected by the problem.
Alleged issues by CTS Labs.
In early 2018, Israeli computer security consultancy firm CTS Labs stated that they had discovered several major flaws in the Ryzen components ecosystem, publicly disclosing them after giving AMD 24 hours to respond and raising concerns and questions regarding their legitimacy, though they were later confirmed by two separate security firms. AMD has since stated that while the flaws are real and will be fixed via microcode updates, their severity was overstated as physical access to the hardware is required to exploit the flaws.