Itanium: Intel’s Great Successor

Added: 2026-05-05

[00:00:02]In June 1994, Intel and Hewlett-Packard  - two of Silicon Valley's largest and most powerful companies - announced an alliance.

[00:00:11]From the union of these two giants, will  spring forth the next generation of CPUs.

[00:00:18]The Great Successor. Chosen to unify  two architectures under one umbrella.

[00:00:24]It was named Itanium and by 2002 Intel had  spent $5 billion on it. In today’s video, we trace one of Intel's most ambitious products.

[00:00:36]## Intel and 64-Bits The x86 instruction set helped  turn Intel into a giant.

[00:00:45]A massive ecosystem had built up around  it. In the 1980s, four out of every five PCs shipped with an Intel CPU. These huge  volumes helped them afford to build big, advanced semiconductor fabs  and produce at the lowest cost.

[00:01:03]Why leave it all behind? But after  shipping the famous Pentium CPU, powerful voices inside Intel indeed began to  assert that the time had come for something new. The foremost reason for doing so  was something called 64-bit computing.

[00:01:21]The "64-bit" part of that phrase refers to  the size of a CPU's "register". At the time, Intel's CPUs were 32-bit processors,  and that limited them in several ways.

[00:01:33]The most prominent limit being that  a 32-bit computer can only use up to about 4 gigabytes of working memory: 2  to the power of 32. Less in practice, because some of that is taken  up by the operating system.

[00:01:49]In the early 1990s, this 4-gigabyte wall  was not a big deal for the consumer market because PC memories topped out at about  128 megabytes. Who can imagine ordinary folks ever needing much more than  that at least in the near future?

[00:02:07]But it was a big deal for graphics  workstations, scientific computers handling precise calculations, and web  servers delivering content over the Internet.

[00:02:17]These are powerful, very expensive  machines that at the time ran UNIX.

[00:02:23]Intel then dominated the PC, but had  no presence in that high end space.

[00:02:28]That space was populated by RISC  chips like Sun Microsystems' SPARC, Hewlett-Packard's PA-RISC, or DEC's  Alpha. Intel wanted to get into that game.

[00:02:40]## Extension versus Blank Sheet So question. Why not just extend the existing 32-bit x86 instruction set so that  it can handle 64-bit registers?

[00:02:50]After all, that is what Intel did with  the prior major transition from 16-bit to 32-bit. It wasn't easy, but the  resulting 386 Intel CPU was a massive success - powering a generation of  PC clones like those from Compaq.

[00:03:09]Intel even tried a similar, very ambitious  blank sheet approach for that 32-bit transition.

[00:03:16]The iAPX 432 was Intel's first 32-bit  architecture. And to skip a lot of words - feel free to read the very long  Wikipedia if you care - that product failed.

[00:03:30]But kind of like invading Russia, history  rhymes. Intel felt that the 64-bit transition would be different. And that this time, x86's  years-old legacy CISC components would hold it back. A lot of extra tooling and rules had  to be followed to preserve that old world.

[00:03:49]AMD and the other x86 cloners were  a factor too. A history of 64-bit computing by Matthew Kerner and Neil  Padgett interviewed Richard Russell, who pointed out that AMD's cross-licensing  agreements gave them access to Intel's x86 work.

[00:04:07]So the way it went was that Intel first releases  a new x86 chip. Then six or twelve months later, AMD releases their version at  a cheaper price. This devalued Intel’s R&D and burned a huge amount  of profits for everyone involved.

[00:04:25]The ghost of IBM and the PC loomed too. There is  no guarantee that Intel will forever control x86.

[00:04:34]The day might come that AMD, Cyrix,  and the other x86 cloners somehow pry control of the standard like  what the PC cloners did to IBM.

[00:04:45]So in Intel's eyes, yeah sure they can always  extend x86. But the reboot-with-a-clean-sheet approach could potentially let Intel surge  ahead of the competition with an architecture that it fully owned. And proponents argued that  Intel now had enough influence to pull it off.

[00:05:04]The debate raged until the late, great Albert  Yu - Intel's general manager of microprocessors, who oversaw development of the 386,  486, and the Pentium - bought in.

[00:05:16]But how to achieve it? Kerner and Padgett  also interviewed Dileep Bhandarkar, who was then an Intel director.  Bhandarkar recalled the company doing a small internal 64-bit effort in 1992  while investigating outside opportunities.

[00:05:32]The computer company DEC tried to get  Intel to take on their RISC chip Alpha, a very fast chip, which they declined. Intel  then suggested DEC make the Alpha in Intel’s fabs, which DEC declined because they just  spent half a billion dollars on a new fab.

[00:05:49]Then in late 1993, HP came knocking on  Intel's door with an exciting new technology.

[00:05:58]## A Post-RISC Technology In 1990, Hewlett-Packard rehired the brilliant Bill Worley to flesh out the future  of their proprietary line of chips.

[00:06:06]Worley used to work at IBM alongside John  Cocke on the legendary IBM 801 project.

[00:06:12]801 is widely acknowledged as the driving  force that kicked off the RISC revolution.

[00:06:18]He then joined HP where he helped produce  one of the earliest RISC instruction sets, Performance-Architecture RISC, or  PA-RISC. The architecture became a growth engine for Hewlett-Packard through  the turbulent RISC wars of the 1980s.

[00:06:35]Worley then briefly left HP  to lead a graphics processor startup but rejoined in 1990 for a  special project. The PA-RISC team recognized that RISC was on the verge  of hitting serious performance limits.

[00:06:50]So a new project initially called  "Super Workstation" was formed to explore new architectures in  the post-RISC beyond. Over time, Super Workstation's work began to intertwine  with that of another team inside Hewlett-Packard: Fine-grained Architecture and Software  Technologies, or FAST an HP internal project exploring and evolving a radical concept  known as Very Large Instruction Word, or VLIW.

[00:07:22]## Meet VLIW Very Long Instruction Word is a term coined by  the brilliant Joshua Fisher while he was at Yale.

[00:07:29]The way he puts it, VLIW describes a  design philosophy. A concept or idea more like RISC, rather than a specific  instruction set like ARM or x86.

[00:07:43]Its goal is for a CPU to achieve as  much Instruction-Level Parallelism or ILP as possible without making its hardware do it.

[00:07:54]What is ILP? It is a way for a single  microprocessor to speed up work by initiating and executing multiple  machine instructions in parallel so that we can try to get more than one  useful operation done per clock cycle.

[00:08:11]Traditionally, high levels of ILP were seen as  infeasible because programs have so many branching conditions: If/else statements, loops and annoying  dependencies that change the path of the code.

[00:08:25]VLIW tries to surpass those shortcomings by running "traces" of the program code.  Using heuristics and user-provided data, the compiler will try and guess how  the user's program might progress.

[00:08:39]That compiler then aggressively  schedules the trace’s instructions for maximum parallelism regardless of  dependencies. To handle mistaken guesses, the compiler adds compensation code  to "backtrack" or fix things up.

[00:08:55]These scheduled instructions are  then packed together and sent to the hardware in "very large words". Ergo the name.

[00:09:03]People initially thought VLIW  computers were impossible. That is because it requires a compiler that  can somehow predict a program’s future.

[00:09:13]The difficulty of producing such compilers  is a recurring theme with this technology.

[00:09:20]## Fisher and Rau Wanting to prove the skeptics wrong, Josh  Fisher left to start a startup called Multiflow.

[00:09:27]In 1987, they produced a line of powerful  mini-supercomputers called TRACE. Over the next two years, they sold and shipped about  100 units to scientific and commercial users.

[00:09:40]Multiflow was not the only startup  exploring VLIW at the time. There was another founded by a brilliant  Indian-American named Bob Rau.

[00:09:50]Rau had led a team at the computer company TRW studying similar Instruction-Level  Parallelism techniques. In the same year Fisher founded Multiflow, Bob Rau and  several colleagues left to found Cydrome.

[00:10:04]Cydrome worked on a VLIW-based "departmental  supercomputer" called the Cydra 5. And while they got it to work, it never shipped as a commercial  product. The company eventually disbanded.

[00:10:20]Multiflow also disbanded. In 1989, the  mini-supercomputer market crashed from over-competition in the category as  well as cannibalization by powerful single-chip RISC workstations called "Killer  Micros". Circumstances trumped technology.

[00:10:38]## A Radical Idea After their startups closed down, both  Bob Rau and Josh Fisher joined Hewlett Packard and the FAST project with the  goal of evolving the VLIW technology.

[00:10:49]At the time, the big thing  in the microprocessor world was an ILP approach called Out-of-order  Superscalar. This approach was arguably pioneered by the aforementioned  John Cocke and Tilak Agarwala.

[00:11:02]Roughly speaking, superscalar involves us adding  independent stations to the CPU, plus extra hardware to grab a lot of instructions, figure  out their various dependencies, and send them to the right stations for simultaneous execution.  This is all done as the program is running.

[00:11:21]Superscalar worked. IBM utilized it then for  their high-performing RS/6000 workstation.

[00:11:29]Intel would later use it for their  Pentium processors. But Rau and Fisher came to believe - quite controversially - that  superscalar is an anchor. An anchor that will blunt the lift that microprocessors  were then getting from Moore's Law.

[00:11:44]Superscalar leans heavily on hardware to  analyze instructions, figure out their various dependencies, and sort them into the  ideal order as the program runs. Such hardware is incredibly complex and power-hungry.  Rau and Fisher bet that it will not scale.

[00:12:03]With their contributions, Super Workstation  produced a new architecture called PA-Wide Word or PA-WW. It performed quite well  compared to what existed inside HP.

[00:12:16]Next then is to design and produce a chip that  implements this architecture. But in this, there were challenges. Worley realized  that PA-WW chips would have to be made in a leading edge fab. In a 2001 interview for  HP Labs, he explained the ramifications of such: > The costs of such a fab implied that the chip  volumes would have to be extremely high. High volumes, as well as the need to attract software  from many providers, implied that the architecture would have to be an industry standard. An industry  standard implied that HP could not do it alone.

[00:12:52]Thus in July 1992, Worley recommended  that HP bring in a manufacturing partner with both prowess and scale.  The obvious partner was Intel.

[00:13:04]On Thanksgiving 1993, HP's CEO Lew Platt  made a call to Andy Grove, asking whether Intel might be interested in working with  HP to make PA-WW the successor to x86.

[00:13:18]Grove said no. HP tried again later,  emphasizing that PA-WW would be fully backwards compatible with both x86  and PA-RISC. This time it worked.

[00:13:32]## Intel and HP Team Up So what did Intel see that got them so interested?

[00:13:35]The HP design team included well-respected  folks like Josh Fisher, Bob Rau, and Bill Worley. And that team had already made  much progress. In a widely circulated quote, Intel's John Crawford told  the Wall Street Journal: > When we saw WideWord, we saw a lot of  things we had only been looking at doing, already in their full glory A PA-Wide Word architect named Rajiv Gupta had  this second golden quote - also widely circulated: > I looked Albert Yu in the eyes and showed  him we could run circles around PowerPC [a competing IBM processor], that we could kill  PowerPC, that we could kill the x86. Albert, he's like a big Buddha. He just smiles and nods.

[00:14:22]Intel would be blind if they didn't also  notice the competitive dynamics. They can convert one of their significant RISC rivals  onto a technology platform that they control.

[00:14:34]And if HP gets on board, then maybe others  like Sun and Silicon Graphics will too.

[00:14:40]Grove was intrigued and ordered a bake-off  between PA-WW and its own internal 64-bit architecture effort. PA-WW won. So they  hammered out a deal, announced in June 1994.

[00:14:56]Hewlett-Packard transfers the PA-WW IP over  to Intel. Intel then designs and produces the first CPUs. HP can then get said CPUs at a  discount to produce enterprise system products.

[00:15:11]There were no solid products, only a  statement of direction towards a future computer architecture. The first processors  were not anticipated to arrive before 1998, but once delivered, they will carry  both companies into the 21st century.

[00:15:28]This was going to be a massive project. Albert  Yu anticipated it costing between $400 to $500 million over its whole life. An  underestimate as it turns out. But Intel can afford it and the results were going to be  amazing. Albert Yu told the press at the time: > By combining our skills... we will  offer the marketplace chips and systems with absolutely unparalleled  performance for the future ## Taking Names Now. I want to pause a bit and talk names. Part  of what makes this all so confusing are the names.

[00:16:04]There are more names here than you can  shake a stick at. And unfortunately they all come out at different times.  I am going to step out of the flow of time and gather them all together  here so that we can keep track.

[00:16:16]So we start off with HP’s Super Workstation, which produces PA-Wide Word. The announced 1994  collaboration with Intel would eventually evolve PA-WW into a new thing called "Explicitly  Parallel Instruction Computing", or EPIC.

[00:16:34]EPIC is an architecture philosophy kind of  like how CISC or RISC are philosophies. So think of it like the philosophy of French  cuisine - a style with recommendations on how to achieve a wanted goal. EPIC likes  parallelism. French cuisine likes sauces.

[00:16:52]EPIC is a direct descendant of VLIW. So it  still transfers complexity from the hardware to the software compiler. The complier still  aggressively analyzes the program code for parallelism opportunities and group  together instructions in big bundles.

[00:17:10]But EPIC strikes a more moderate  tone by admitting that sometimes the hardware is in a better position to  do certain things in runtime because of access to program variables. So EPIC  accommodates hardware in the CPU for that - but not so much to make it  as complex as a superscalar chip.

[00:17:29]Multiflow and Cydrome's VLIW compilers  were also too tightly bound to their microarchitectures' hardware. EPIC  addresses this rigidity with something called "templates" - which help define  which instructions can be bundled together.

[00:17:45]Now that is EPIC. The next term to  introduce is the IA-64 instruction set architecture. EPIC is to IA-64 as what  RISC is to PA-RISC or SPARC. A specific instruction set implementation of EPIC,  defined and owned by both Intel and HP.

[00:18:05]So to continue the cooking metaphor, you  can think of it as like a French cuisine cookbook - demonstrating various techniques  and recipes for cooks to make French dishes.

[00:18:17]After that, we go to the individual  chips. The French dishes themselves, as served by the restaurant. Intel expected  its first IA-64 chip to hit the market in 1998.

[00:18:30]Internally, this first IA-64 chip had the  codename Merced after a river in California.

[00:18:37]In October 1999, Intel would announce that the  chip would be officially named Itanium. Intel said at the time that the name conveys the processor's  unique strengths and power while retaining the "-ium" word endings for brand consistency.  Netizens almost instantly dubbed it the Itanic.

[00:18:58]## Reactions Anyway. Back to 1994 and the flow  of time. Outside analysts saw the collaboration's potential - citing the  two companies' talents and capabilities.

[00:19:09]Hewlett-Packard was top two in the  workstation and server markets, where Intel was then weak. And of course,  Intel was the juggernaut of the PC industry, trying mightily to get into the  workstation and server industries.

[00:19:24]Analysts looked at how the collaboration might  have on IBM, which backed its own PowerPC line of RISC chips. Andrew Allison of the "Inside the  Computer Industry" newsletter told ComputerWorld: > I would imagine that IBM is not terribly  thrilled with it... It’s probably the only combination that is virtually guaranteed to  have the horsepower to stand up to PowerPC.

[00:19:48]Intel didn't outright say it - and  they would later deny to have ever implied such a thing - but they  also positioned this new family as the future successor to x86. One  VP at a Boston consultancy said: > "Intel is smart enough to know when it’s  time to be at the end of the x86 line."

[00:20:07]The Microprocessor Report echoed the notion  that the end was now in sight for x86.

[00:20:13]This new architecture will supersede both it and PA-RISC before trickling down  to the mass market. They write: > We expect that, in about 10 years, Intel  will stop making pure x86 chips in favor of [the new chips]. Intel will continue to  milk the x86 cash cow as long as it can... > Intel’s P6, due in late 1995, probably will  be the last pure x86 core that Intel develops ## Disagreements Not everyone agreed with that.  Shortly after the announcement, Nick Tredennick wrote up a dissenting view.

[00:20:52]He argued that the two companies  had shot themselves in the foot by transitioning architectures and  pursuing the VLIW "technofad".

[00:21:01]He pointed out that big architectural  shifts require developers to recompile their software. Which they hate  doing because it’s never smooth.

[00:21:10]And that the complicated hardware  will also need extremely complicated compilers. Neither of which have  good histories of on-time delivery.

[00:21:20]And that switching away from x86 would be  walking the same mistaken and failed path that IBM did when Big Blue tried to lock down the  PC ecosystem with the Micro Channel Architecture.

[00:21:34]Add to this boiling bone broth the collaboration's  high expectations, which towered over K2.

[00:21:42]Robert Colwell is a legendary CPU  designer who previously worked at Multiflow. He then went to Intel  in 1990. In his memoirs, he wrote: > In essence, [the Intel design team in charge  of IA-64] were told that their mission was to jointly conceive the world’s greatest  instruction set architecture with HP, and then realize that architecture  in a chip called Merced by 1997, with performance second to no other  processor, for any benchmark you like.

[00:22:14]Merced will also do all these things  while being fully compatible with legacy software of both x86 and  PA-RISC. This sounds ambitious.

[00:22:26]Colwell was not alone in his doubts.  Intel's chief of corporate strategy at the time was David House.  While he approved the project, he would later say that its sheer scale - and I  quote - "scared the everloving bejesus out of me".

[00:22:42]## Merced Intel sold chips to HP, but they  never worked together on this level.

[00:22:47]HP is famous for its consensus-based management style. Intel on the other hand is just as  famous for "constructive confrontations", where people are expected to challenge  each other bluntly, promptly and with data.

[00:23:03]So the two arm-wrestled over what functions should be handled by the software or hardware while  simultaneously ramping up their teams with new, relatively inexperienced  people. There was tension.

[00:23:15]The difficult experience was either so traumatic  or constructive that HP took the sole lead for the second generation of IA-64 chips. This  particular chip project was code-named McKinley.

[00:23:29]The original plan was to release  Merced in 1998 and fab it with Intel's 250 nanometer node. But  then the chip design was found to be spilling beyond the limits of  what can be fabbed. Like a muffin top.

[00:23:43]So the designers took out transistors  allocated for memory cache and x86 compatibility. Removing the latter  was made easier after the much-faster Pentium Pro released because of weak  x86 performance relative to that beast.

[00:23:59]Even so, there was still spill over. So it  was decided to go to the 180-nanometer node instead. The transistor shrink would let  them put the whole design onto a single die. The cost however was a six month  delay, pushing the ship date to 1999.

[00:24:16]Things progressed. In October 1997,  the two companies introduced EPIC and IA-64 to 1,500 computer designers at the  Microprocessor Forum. They talked about EPIC's key architectural choices and emphasized  its speed relative to existing RISC chips.

[00:24:35]Intel also shared a release date for Merced: 1999. They said it would have industry  leading performance, full compatibility with the old 32-bit architecture, and  have a complete solution stack at launch.

[00:24:52]Several big software developers announced  their participation in the IA-64 ecosystem.

[00:24:58]Microsoft agreed to have a 64-bit version of  its Windows NT operating system available at release. Sun said it would make their  Solaris OS available on Merced chips.

[00:25:09]And to raise the hype even more, presenter  and Intel Fellow Fred Pollack teased the second-generation McKinley chip, saying  that it was going to "knock your socks off".

[00:25:20]## P7 When Colwell arrived at Intel back in 1990, he helped found the company's  second design team in Oregon.

[00:25:30]That team - working in friendly competition  with a team in Santa Clara - began on a product code-named P6. It would be released  in 1995 as the 32-bit Pentium Pro.

[00:25:44]The Pentium Pro was a remarkable chip.  Despite being fabbed on the same process as its predecessor (P5), P6 ran twice as fast  thanks to the inclusion of ideas like out-of-order superscalar, which to remind you, searched more  aggressively for instructions to parallelize.

[00:26:04]The Pentium Pro brought Intel's x86 architecture  neck to neck with some of the fastest RISC chips.

[00:26:11]It also opened the door to the workstation  market by enabling the "personal workstation".

[00:26:17]Such personal workstations - running  Microsoft's Windows NT or Linux - cost half that of the old-school UNIX-powered  workstations. They grew rapidly in 1995, eating into the low end of the market.

[00:26:32]Unfortunately, internal politics interfered with  the Oregon team's pursuit of this opportunity.

[00:26:38]Colwell remembers being told that IA-64  will eventually replace the 32-bit lines, so why keep working on the old legacy stuff?

[00:26:46]To Colwell however, the Pentium Pro  showed that the 32-bit architecture still had plenty of juice. With no 64-bit  killer application on the immediate horizon, a premature switch might leave the  market to AMD and other competitors.

[00:27:02]He also argued that Merced had so many  new things going on that there was no chance that it would all work right on  the first try. He felt Intel should have returned the chip to the lab as a long-term  research project to iron out its kinks.

[00:27:18]In the end, management could not decide on a  coherent strategy on how to resolve the conflicts between the Oregon team working on 32-bit and  the Santa Clara team working on 64-bit Merced.

[00:27:30]At first, they were content to just stand  aside and let the best one rise to the top.

[00:27:36]However this backfired, because Merced had  to be compatible with the 32-bit stuff. With Colwell and the Oregon team still working on  it, that goal became an ever-moving target. So the Santa Clara team tried to "freeze"  the specification, which Oregon hated.

[00:27:54]In the end, management separated the children:  64-bit for the more powerful server chips.

[00:27:59]32-bit for everything else including workstations.  That’s the strategy Intel would follow henceforth.

[00:28:06]By the way, I highly recommend Colwell's  book, "The Pentium Chronicles", where he talks about these worsening dynamics between  Santa Clara and Oregon. It is a strong read.

[00:28:17]## A Second Delay Soon after the October 1997 presentation at the  Microprocessor Forum, a new problem emerged.

[00:28:23]A source told CNET at the time that  Intel severely underestimated the chip's complexity. The Wall Street Journal  later reported Intel struggling with various signals arriving at parts of the CPU at  the wrong time, creating speed bottlenecks.

[00:28:39]This was amplified by Intel targeting an  exceptionally high 800 megahertz clock rate.

[00:28:45]Tweaks made to fix bottlenecks in  one module caused ripple effects in other modules, making debugging endlessly tricky.

[00:28:53]There are rumors of other things, but I  won't go into them. Whatever the thing was, it was serious. By mid-1998, the  company had to announce that it was pushing Merced's release from late 1999  to mid-2000. Which means servers do not reach actual customers until Q4 2000.  New CEO Craig Barrett told the press: > Our best assessment is that the project is  a bit bigger and complicated than we assumed it would be... we are pleased with progress.  There's not a basic problem with the technology.

[00:29:26]This second delay means that Merced is scraping  up against the second-generation IA-64 chip - the one that HP is designing code-named McKinley. It  was scheduled to enter mass production in 2001.

[00:29:42]Intel finally successfully taped  out Merced in summer of 1999 and demonstrated it in the fall at its 1999  Intel Developers Forum. Shortly afterwards, the fabs started learning how to produce the new  chip, with early versions seeded to developers.

[00:29:59]## Transition Plans Both Intel and Hewlett-Packard - perhaps expecting  this might happen - went to their backups.

[00:30:04]At the 1998 Microprocessor Forum, Hewlett-Packard  unveiled a "transition plan" towards IA-64.

[00:30:11]They would continue releasing additional  PA-RISC chips for the next five years until 2003. Customers can choose which  chip they want in their server.

[00:30:21]This was not ideal. A former HP executive  remarked that they had to do all sorts of tricks to extend PA-RISC. The delays and distractions  associated with getting out IA-64 allowed rival Sun Microsystems to leap ahead in the web server  market during the wild late 90s internet boom era.

[00:30:41]And as for Intel, the chip giant revitalized  market revenues of its 32-bit architecture in 1998 with the introduction of the Celeron  and Xeon lines. Market segmentation.

[00:30:54]The former targeted value-minded consumers  who otherwise bought cheaper chips from AMD, Cyrix and other cloners. The first Celeron flopped because it basically had no cache but  later iterations performed very well.

[00:31:09]The latter chip, the Xeon, targeted  the medium to high-end server market with faster clock speeds, larger  caches and higher cache bandwidth.

[00:31:19]So when Merced was announced to be delayed, analysts noted that it was not a huge  deal and that the Xeon can hold on as a "placeholder". As we will later see,  that turned out to be an understatement.

[00:31:33]The delay did give OS-makers like  Microsoft and the UNIX vendors time to port for Merced/Itanium. But even as  something like a "race" developed, actual application developer interest remained tepid.  One Wells Fargo system architect said in 1998: > We have a few applications  that could benefit from Merced, but probably not anytime soon ... first we’ve got to take care of Year 2000 compliance issues.  Maybe in 2001 we can look at Merced ## Itanium in 2001: The Revolution is Here After 7 years and $5 billion spent, Intel  finally launched Itanium in the summer of 2001.

[00:32:13]Recognizing that their 32-bit  products were still going strong, Intel tried to position Itanium as a powerful  but revolutionary product for the "most demanding enterprise and high-performance computing  applications" as their press release said.

[00:32:29]So yes, while it might take some additional  work at the start, those who do will be rewarded. They commissioned a white paper to  identify "sweet spots for early adopters", which included technical computing,  large databases, and complex analytics.

[00:32:45]To the press, Intel worked hard to emphasize  that this was just the first step of a long journey and that the ecosystem adoption thus  far at this early stage was pretty impressive.

[00:32:56]On the hardware side, they highlighted buy-in  from a spectrum of computer manufacturers.

[00:33:02]Some 35 Itanium-based models were said  to be released by 25 companies like Dell, Compaq and Silicon Graphics throughout 2001.

[00:33:12]Intel also highlighted that Itanium systems  can run four compatible operating systems: Two 64-bit versions of Windows,  HP's proprietary UNIX variant HP-UX, IBM's proprietary UNIX variant, and  certain commercial Linux distributions.

[00:33:31]With all this backing from the big companies, people presumed that Itanium would take the  market. A 2000 market report from MicroDesign Resources had predicted that IA-64 chips  would have 60% of the server market by 2003.

[00:33:48]Unfortunately, Itanium took too long of a  path to the market. Soon after its debut, it was outshone by several new 64-bit RISC like  Sun's UltraSPARC III and IBM's Power4 chips.

[00:34:02]Microprocessor Report nominated the Itanium for its Best Workstation/ Server  Processor award, but wrote: > But while other high-end server processor  designs are moving to glueless multiprocessing, simultaneous multithreading,  chip-level multiprocessing, and integrated memory controllers, the  Itanium system architecture is beginning to show its age. Perhaps the design has been in  development too long and has had too many cooks.

[00:34:32]Another major issue was that there was not  a lot of Itanium-native software. And while Itanium can run 32-bit x86 software, it  unfortunately did not do it that well.

[00:34:44]IA-64 is so different from x86 that  emulation means recreating the whole thing from scratch. The more you try to  force the former to act like the latter, the more you are giving up  its own inherent advantages.

[00:35:00]Considering the chip's high  price, disappointing performance, and the looming arrival of a  faster chip the following year, it is surprising that the first iteration of  the Itanium sold even the few units that it did.

[00:35:13]There are a few who say that Itanium did  (allegedly) kill one of its big RISC rivals, the DEC Alpha - once heralded  as the world's fastest chip.

[00:35:23]After Compaq bought DEC, they wanted  to consolidate to a single 64-bit platform - which was Itanium because that  was all that Intel had at the time - and sold the Alpha IP to Intel. Does that  mean Itanium killed Alpha? Not sure.

[00:35:39]A few people are nostalgic about the Alpha,  but chip R&D is expensive, DEC was not doing well then, and it was not like the chip was  doing all that great before Compaq nixed it.

[00:35:51]## AMD Befitting the fast follower, AMD  too wanted to get into the server business. They had 18% of the 32-bit market  but zero in servers. That meant going 64-bit.

[00:36:05]Hearing that Intel was doing something brand  new for 64-bit, AMD approached Intel for an early look at the Itanium architecture.  But as I mentioned in passing, Intel had intentionally carved out Itanium from AMD's  cross-licensing agreements. They were rebuffed.

[00:36:22]So what to do next? Atiq Raza - who joined  AMD as COO from its acquisition of the CPU company Nexgen - explains in his oral  history for the Computer History Museum: > Everybody said we're going to  get screwed. Itanium is going to take over the world. So I said, "Okay.  I find it very weird that basically they have abandoned the x86 and are doing a  different instruction set for 64-bit.

[00:36:47]We should also consider doing a different  instruction set if that's the case."

[00:36:52]So AMD investigated various partners - SPARC,  MIPS, PowerPC and DEC - to see whether they can do something. While those ecosystems had  existing user bases that AMD can leverage, 32-bit x86 software did not run  well on them in emulation mode.

[00:37:11]Eventually, AMD came to believe  that Intel had made a mistake.

[00:37:15]Developers hate recompiling software  and users hate being forced to adopt something new unless for some compelling  reason. IA-64 didn't seem to be it.

[00:37:27]VLIW's roots were in academia. And while  Multiflow did sell well to corporates, it showed its best colors on numerical and  scientific workloads as those programs tend to have more repeated loops, ILP opportunities  and predictable control flows. For more generalized work like in the business  space, VLIW’s gains were not as obvious.

[00:37:52]If Intel really did err in going down the route  to Itanium, then AMD suddenly had an opportunity.

[00:37:59]So Raza went to a brilliant chip designer who  joined AMD from DEC named Jim Keller, and said: > "Jim, life and death for AMD. We  do an x86 extension to 64-bit. You have to write the spec and you have  to do it with very little time."

[00:38:18]Keller - who cranked on this day and night -  thus is one of the major authors of the x86-64 spec - later known as AMD64. Which I would  say is by itself a killer legacy, but Keller has since gone on to do a bunch of legendary  stuff at Apple, Tesla and more. Living legend.

[00:38:38]In October 1999, AMD announced x86-64 to the  world. This was a major divergence from Intel.

[00:38:45]AMD assured the market that  their 64-bit transition will be a "simple change" fully  compatible with 32-bit x86.

[00:38:54]AMD - never one to miss a snarky comment  at their rivals - criticized Intel for "forcing" the Itanium design onto the OEMs.

[00:39:04]Ron Curry, Intel's director of  marketing for IA-64 products, responded by insisting that Itanium  too will have x86 compatibility.

[00:39:15]He then went on to compare AMD's strategy  to trying to soup up a Volkswagen with wider tires and a faster engine. I get where he is  driving with this but still find it amusing.

[00:39:28]The looming threat of AMD's entry  into the 64-bit space pushed Intel to double down on its second-generation  IA-64 chip, the one codenamed McKinley.

[00:39:41]## Itanium 2: This is Ready In 2002, Intel CEO Craig  Barrett rebooted the project.

[00:39:45]McKinley was officially  announced as the Itanium 2, made an official member of the Intel  lineup, and released in late 2003.

[00:39:55]Then-CEO Paul Otellini predicted sales of  100,000 units, telling security analysts: > At the risk of getting  myself in a lot of trouble, I'm going to declare this the year of Itanium The Itanium 2 was indeed an improved  product. It performed better on benchmarks.

[00:40:14]Largely because of a larger bus with three times the data bandwidth of the first  Itanium and bigger L3 cache.

[00:40:23]For the redux, Intel sharpened the messaging to  aim squarely at Sun and their high-end UltraSPARC III-based server systems - then the market leader  in UNIX systems with nearly 30% market share.

[00:40:36]Intel's product news release repeatedly compares it favorably to the UltraSPARC III.  Sun must not be happy about that.

[00:40:44]Second, Intel highlighted growth in the  software ecosystem. Applications were now available from Microsoft, Oracle, Reuters,  and BEA. They also claimed that the chip is compatible with more operating systems than  any other high-end enterprise server platform.

[00:41:00]And Hewlett-Packard was giving it their all.  They developed an Itanium 2-based high-end server called the Superdome that can run a variety  of operating systems - not just HP-UX but also Windows and Linux - to help transition  their customers over to this Intel stuff.

[00:41:18]But even as early December 2002, there  were concerns by outside analysts that HP might be the only server vendor  to go so far in adopting the Itanium.

[00:41:31]In November 2003, Intel's director of  business-critical systems marketing told CNET that Itanium was on the brink of broader use and that 2004 was going to be  a "very strong watershed year".

[00:41:45]## Rise of the Compute Cluster In an earlier time, I think it might have worked.

[00:41:47]I think Intel really did have the market  power then to drag people to Itanium. The growing internet tech giants might  have bought plenty of expensive Itanium-powered computers for web servers,  and Itanium could have been on its way.

[00:42:02]But times were changing. Tech giants like Google  were turning away from big mainframes towards what are called "compute clusters". Such clusters  were powered by cheap commodity hardware and the open-source Linux OS and then networked  with software to act like one chonk computer.

[00:42:22]Such compute clusters can be cheaply  scaled up to serve billions of people.

[00:42:26]Buyers don’t have to pay a tax  to a proprietary systems vendor.

[00:42:30]Clusters also tend to be more resilient  against physical hardware failures.

[00:42:35]Big mainframes still have their  place but clusters were the future.

[00:42:40]That means cheap commodity hardware, which  ironically enough meant x86 Pentium - later Xeon - CPUs. In the end, Itanium's biggest  competitor was another Intel product.

[00:42:54]## AMD's Victory In April 2003, AMD released the K8 Sledgehammer  core in the Opteron and the Athlon 64.

[00:43:02]AMD counted on the 130-nanometer Opteron to  help it gain traction in the corporate market.

[00:43:08]They held it out as the "evolutionary" path for companies with legacy code  to get to 64-bit computing.

[00:43:16]Despite its groundbreaking features  and Sun's support, the chip did not sell as well as anticipated. System sales  by mid-2004 did beat Itanium, but lagged Xeon's by a country mile. Basically none of  the big box vendors made an Opteron server.

[00:43:32]This sus behavior is what in part  led CEO Hector Ruiz to eventually sue Intel again for alleged  anti-competitive practices.

[00:43:41]But Opteron and Athlon 64 did  force Intel's hand. In early 2004, Craig Barrett told developers that  they were adding 64-bit address extensions for their server Xeons.  Desktop chips, the following year.

[00:43:57]Intel ended up adopting AMD's 64-bit extension,  with some minor differences. It was the first time that a company other than Intel  made a major addition to the x86 spec.

[00:44:10]Isn't it ironic? Intel produced Itanium in part  because they were afraid that AMD and the cloners might pry away control of x86. But making Itanium  eventually led to that very thing they feared happening! Fortunately for them, they still had  Xeons (and their special discounts to vendors).

[00:44:30]Several analysts had projected Itanium server  sales to reach $14 billion by mid-2004. The actual sales number then was about $600  million. Outside of Hewlett-Packard, no major systems vendor was selling  these Itanium systems at volume.

[00:44:48]## Conclusion Intel leadership long insisted that Itanium is a long term play. In a 2005 oral history  for Stanford University, Albert Yu said: > I think Itanium has not failed. I think  the Itanium chapter has not been written yet.

[00:45:03]Later on, he says: > Itanium was never intended to be a replacement  for Intel Architecture. It was never thought of that way. It's always to be for high end servers.  And I think there probably some confusion.

[00:45:15]Some people might think that we're going to  take Itanium to replace Intel architecture.

[00:45:20]That's never been the intention. It will be an  additional architecture, and that was the intent.

[00:45:27]Chairman Craig Barrett echoed the sentiment when  he retired in 2009. He said in an interview: > You guys have had a lot of  fun with it in the past... The ultimate verdict is probably  going to be 10 years from now In 2000, the company posted a roadmap document  that said that the IA-64 architecture would last for 25 years. It didn't quite  get there, but it got darn close.

[00:45:53]A big reason why was Hewlett-Packard  - which quickly standardized on the Itanium. They were its dominant user - buying 85% of production - and depended on it quite a  bit. Their HP-UX OS only runs on Itanium.

[00:46:07]This became a problem as the Itanium ecosystem  declined. So HP went to great lengths to keep this thing huffing and puffing even as  software developers started dropping support for Itanium systems: Red Hat in 2009,  Microsoft in 2010, and more since then.

[00:46:25]The biggest drop-out occurred in 2011 when Oracle  halted Itanium development and called the product "end of life". This led to Intel getting huffy and  a lawsuit from Hewlett-Packard three months later.

[00:46:38]It is thanks to this lawsuit that we  learned that HP agreed to pay Intel $690 million over the span of 2 deals to  keep producing Itanium chips until 2017.

[00:46:51]HP won the lawsuit by the way.

[00:46:54]Development on Itanium continued - we have  a Itanium 9100, 9300, 9500, and 9700 series.

[00:47:01]But it was clear to everyone that the bulk  of Intel's resources would be spent on the x86-based Xeon. And today, the Xeon is indeed  one of the company's biggest product lines.

[00:47:13]But the day had to come. And in 2017 it finally  did, Intel announced that that Itanium 9700, codenamed Kittson, would be the end. The  last to be shipped in 2021. And so it was.

[00:47:26]With all that being said, I do applaud Intel  for having the ambition, balls, and billions to throw at something like this. For years, CPUs  got faster from improvements in both clock speed and architecture. After going superscalar, what in  the latter was left? Itanium's failure locked x86 into the market - and in part paves the way  for the stasis to come later in the decade.