Intel: Windows on ARM Won't Run 'Legacy Apps'
Windows 8 will arrive in two flavors: one for x86 with legacy support (Windows 7 mode), and one for ARM without legacy support.
Tuesday during Intel's Investor Meeting 2011 in Santa Clara, California, senior vice president and general manager of the Software and Services Group Renee James said that Windows 8 will arrive in two versions: the "Windows 8 Traditional" for the x86 platform and another version that runs on ARM's architecture.
According to James, the x86 version will support legacy programs and include a "Windows 7 Mode." The ARM version will not.
"[Windows 8 traditional] means that our customers, or anyone who has an Intel-based or an x86-based product, will be able to run either Windows 7 mode or Windows 8 mode," she said. "They'll run all of their old applications, all of their old files – there'll be no issue."
But on ARM, there will only be the new experience centered around mobile platforms, specifically tablets and some limited clamshell devices, with no legacy OS. "Our competitors will not be running legacy applications. Not now. Not ever," she said.
Intel also has the upper hand having established a close relationship with Microsoft over the last twenty years. In fact, there's an on-site development team in the Microsoft HQ that actually works "deep in side the OS to make sure that the platforms, and the features, and the new instructions – whatever new thing we're inventing – is ready to go at the time of introduction of the latest Microsoft environment."
"We've been working for the last couple of years – very, very focused – on Windows 8," she told the audience. "I'm very excited about it. We've been working on it for a long time. There's a lot of exciting new features and things about it that I think are going to be great for users, great for the PC and tablet industry."
She also pointed to Intel's unified architecture, that applications and operating systems can run from one generation of Intel platform to the next. Applications can even be executed across multiple versions of Intel's architecture including Atom, Xeon and Core. That's not the case with ARM-based solutions.
"There will be four Windows 8 SoCs for ARM," she said. "Each one will run for that specific ARM environment, and they will run new applications or cloud-based applications. They are neither forward- nor backward-compatible between their own architecture – different generations of a single vendor – nor are they compatible across different vendors. Each one is a unique stack."
Windows 8 for x86 will run both legacy and SoC.
James is also doubtful that consumers will flock to an ARM-based, non-legacy PC experience based on past consumer behavior.
"People do not change their usage models that frequently," she said. "We've done a lot of studies – you go back and you look, and on average it's about 10 years between people changing their usage patterns. So even though we see a huge change in the way people are using applications from the cloud, there's still a long tail on legacy – something that's uniquely a value proposition from Intel."

Compatibility is something us from the 'PC-era' take for granted. I'm not looking forward to relying on any other companies (beyond Intel/MS) to provide the updates necessary to run on my new gear! Screwed we are...
Well at least I can still look forward to Windows 8 for ARM.
Kudos to intel and AMD in realizing this (or maybe they're just happy they're the only real x86 license holders). It sounds like intel has a card up its sleeve, i just hope it isn't another atom.
Not saying she's wrong, but I would prefer to hear from Microsoft on this matter, not Intel.
And by saying they will not have forward or backward comparability within the ARM architecture i simply cannot believe, why would Microsoft branch to ARM with one off designs for specific SoC sets, no not a chance.
Don't forget the "Windows 8 64bit Samsung SOC ARM Cortex A9+ Dual Core professional retail"
When consumer showing up their money wanting an OS that support both combined, I dont see how Microsoft gonna reject this, especially there is a huge advange if your OS can run both ARM/x86 base apps by using emulation regardless of what the CPU(Arm/x86).
Apple hasn't shipped a PowerPC Mac since 2006 and yet they still support PowerPC emulation in Mac OS 10.6.
Windows 8 is going to bomb if they don't get this right. Try explaining to a consumer why he can't install the same programs on his desktop and his tablet even though both run Windows 8....
Btw: Do phone makers have to modify Android for different SoCs? Is Intel serious that ARM based SoCs aren't compatible with each other?
On phones, MS "solved" this issue by tacking a CE, Mobile, and then Phone on the end of the moniker to indicate that it was a different OS. That wouldn't work in the case of tablets, where you're supposed to be running full applications.
The only solution seems to be running a virtual machine, as Apple did post-PowerPC, at the cost of slowing performance. You might not notice that on legacy apps anyway.
Games? Forget it. Emulation would make them too slow and the various bits get written in optimized assembler to goose speed even more. The graphics rendering might need to be redone for tablet graphics "cards" as well. It's probably more work to rewrite and recompile it all than it would be worth until (if) the ARM tablets take a substantial market-share.
Seriously, few need to run old software anyways. Only businesses require legacy software.
I might be wrong on this but logically I think I'm not (if I am please correct me). Legally, an emulation software would most likely require an x86 license from Intel. Having an x86 emulation for ARM to run legacy apps would be AGAINST Intel's interest. So Intel would is not going to 1) make an emulator 2) license it to eg. Microsoft to make one.
This is quite unfortunate since one of the main reasons for Win 8 on ARM would have been the ability to run all the applications. However you can understand Intel's decision.
Considering people have managed to emulate complicated consoles such as the PS2 maybe we'll see illegal x86 emulators for Win 8 ARM.
i run acdsee 8 pro for home use. i cant upgrade even though i want to because they took out key features in newer releases that make them unusable.
there is allot of software that i use thats old with no viable upgrade solution
not to mention games.
Except we already have an x86 emulator, known as Bochs or QEMU. I've run Windows 95 x86 on my Sun UltraSparc III+ using Bochs before, it wasn't pretty and it was missing network support but it worked. And this is from opensource, imagine what would happen if someone actually wanted to create an optimized 32-bit x86 on ARM emulator.
For the "different SOC" you saw, that really ~really~ depends on drivers. Each different SoC will require a different set of drivers, namely in the memory controller and video processor departments. Android runs into the situation and they've made immense headway in incorporating lots of vender driver support into the Android kernel or as a loadable module. Remember ARM isn't a single CPU, its a licensable architecture / ISA. Different implementations of the ISA will require customized drivers from the vendors.
there is allot of software that i use thats old with no viable upgrade solution
not to mention games."
Well then, I guess that'd place you in this group:
"FEW need to run old software"