ARM is an ISA, and an ISA that doesn't have a company that is powerful enough to produce something competitive. I'm not saying it is impossible for the ARM architecture to be competitive, I'm saying that there isn't an ARM implementation that is competitive. I'm saying that there likely won't be one that is competitive as there just isn't a company that has the resources to make it such (or a company that is willing to).
Beating intel isnt impossible. The guys at VIA have delivered a better lowend chip than atom, despite a huge process handicap and despite an engineering team and R&D budget that is ridiculously small compared to what intel has.
But Samsung and Microsoft are not exactly small players, they certainly can afford the resources. I also think nVidia might well pull this off, they have assembled a team of very experienced CPU guys and nVidia arent new at designing complex highend chips.
Now beating intel in single threaded integer performance will be hard for anyone not called IBM, but you dont need that to be competitive. A few things are happening at once; the importance of raw cpu performance is dwindling, software is increasingly becoming parallel and much of the heavy stuff is being offloaded, either to the cloud or the gpu's.
Therefore nVidia (or MS or samsung or anyone) doesnt need a cpu that outperforms intels highest end cpu's in single threaded integer performance. For desktop, they need something that is faster than the current purely mobile ARM designs and that achieves something Core 2 class. That shouldnt be that hard, in fact a cortex A15 with a desktop class IO and memory interface would probably get you there already. Add to that a better GPU and GPGPU capabilities than intels, if needed throw more cores at it, while still retaining a smaller (therefore cheaper) chip that is probably a lot more energy efficient too, and you have a competitive chip. Not core i7 beating, but something that can compete with intels mainstream product range, selling in to notebooks, all in ones and desktops running ChromeOS or windows for ARM. And that is going to undermine intels fat monopoly margins.
For servers, competing with intel should be easier even. Many workloads, especially "cloud servers" are all about performance/W and performance/$. Small wonder Atom servers are getting so popular, you even see 512 cpu servers based on atom. That is, despite Atom currently not even having ECC support (ouch), despite having to chose between virtualisation, 64 bit support and dualcore. You cant have it all today in an atom, but thats not stopping big OEMs and startups alike to design servers around it.
Building an ARM chip that performs like an Atom on server loads, at similar or lower price points and power consumption is very doable. Id even say 'easy'. And you can do so while offering the features that intel deliberately disables on atom to help save its xeon margins. Marvell is working on this, Im sure nvidia is, and it doesnt seem to be something particularly unlikely to succeed.
Could intel react? Sure, they could drop some of the restrictions on atom. And allow $30 atoms to go in to server sockets where they used to sell $300 xeons. That will help their margins.
Then there is HPC; nvidia is already making some inroads with tesla. Why should it rely on x86 cpu's to feed their tesla's? You could cram a dozen cortex a9 class integer cores in a single fermi and it would barely have an impact on power consumption or die size. Now Cortex is probably too slow for this, project denver should fix that and offer nvidia a complete HPC building block.
As for the "failed" architectures. Itanium is still alive and kicking. It may not be a dominating force in the market, but it is there and it taught valuable lessons to the intel engineers.
Its not quite dead, their new ISA just failed to deliver a better cpu than the competition, including the x86 competition. So from a "merchant' 64 bit server cpu, it has become an HP only chip to replace HPs previous risc cpu's. In that sense, its an utter failure, it delivered nothing that couldnt and hasnt been done with existing ISAs. It just costed 5 or 10 billion dollars more to get there.
The other failed attempts I would a credit to the fact that they were side projects, and not Intel's bread and butter.
You mean they all failed to become intels bread and butter. They where all destined to replace x86, with the exception of their ARM chips.
The more Intel sees the squeeze to move away from x86, the more money they are going to invest in the transition.
Sorry, in what transition?
Just because they haven't been successful in their new ISAs, doesn't mean they can't be. It is far more likely that they as a multibillion dollar company will be capable of adapting as opposed to joe's garage company coming in and taking them out.
VIA's garage company did just that from a technical POV. As AMD is doing arguably with their fusion chips. Besides, if you look at the ARM ecosystem, thats not exactly "joe's garage". Its a sky scaper that totally dwars intel's shop in size and R&D expenditure. Dont forget the ARM business model, where 100s of companies essentially pool a big part of their R&D money in to ARM holdings thats doing a lot of the design for all of them. Combined, they outsell intel 10-1. Thats why a standard ARM core comes with a ~$0.2 core license. I suspect an Atom chip carries a per core R&D cost that is closer to $5 or $10. Its certainly more than the silicon cost of the chip. The same problem that AMD and VIA have competing with intel (volume) is going to be intels problem competing with ARM.