Processors 101: Understanding ARM and Windows RT
With the announcement of Microsoft's Windows RT tablet, ARM processors are very much in the news. What exactly is an ARM processor, and why is it important?
With Windows RT set to launch in September, coupled with the Surface tablet Microsoft announced in June, ARM processors have become a hot topic.
Surface tablets, come in two forms: Surface RT (the RT stands for Run Time) will use an Nvidia ARM processor, while the slightly larger but more powerful Surface Pro will run on an Intel's third-generation Core i5 CPU..
None of this, of course, answers two very basic questions users are asking: What the heck is an ARM processor and why should I care?
Understanding ARM Processors
ARM processors have a history that dates back to the 1980s, when Acorn Computers designed the original architecture. Acorn since developed into ARM Holdings, which licenses the processor to manufacturers. ARM stands for Advanced RISC (reduced instruction set computer) Machine, which again tells the average person absolutely nothing.
All you really need to know is that an ARM processor is small, relatively cheap to produce and has a low power usage. These three attributes make ARM processors well suited to mobile devices. If you own a smartphone, portable game console, netbook or MP3 player, chances are it runs on an ARM processor.
When used in tablets, ARM processors provide longer battery life because they use less power. ARM processors also produce less heat than larger Intel processors, so the tablet casing can be thinner. And while they are not as fast as Intel PC or notebook processors, ARM processors still provide reasonable speed, especially when it comes to mobile computing tasks.
ARM, Intel Core and Legacy Application Compatibility
The ARM processor does have some disadvantages compared to an Intel processor. Avoiding a long, complicated, and unbelievably boring explanation, ARM processors are not compatible with applications designed for programs written with Intel's x86 architecture. That includes all versions of Windows before Windows RT.
In other words, if you own a large library of pre-Windows 8 applications, such as games, image-editing software packages with cameras and camcorders, and drivers for older printers and other electronic devices, don’t expect to run them on Surface RT Microsoft had to make some significant tweaks just to Windows and Office to make RT compatible with ARM processors.
This doesn't mean that the Surface tablets are standalone products like ereaders. The tablets will be compatible with any portable device that runs on an ARM processor, so you'll be able to connect it to business card scanners, cell phones and similar devices. Newer model wireless printers and peripherals should be ARM-compatible, not because of Surface, but simply because of the prevalence of ARM-powered portable devices now available.
This explains why Microsoft decided to develop two versions of the Surface tablet. If you're looking for a light tablet with long battery life, and you don’t mind starting your app collection from scratch, look to the 9.3 mm, 23.85 ounce Surface RT. Running off Windows RT, the Surface RT will run all apps found in the Windows Store, which will replace legacy applications. You'll be able to do any task you use legacy apps for, you'll just be using applications designed for Windows RT and the ARM processor.
If, however, you want laptop-levels of power, connectivity to legacy devices, and a processor capable of running legacy apps, the 13.5 mm, 31.85 ounce Surface Pro may be more appropriate for your needs.
While some critics have suggested Microsoft needlessly complicates the Surface tablets by offering two versions, the company may be looking to kill two birds with one stone.
The Surface RT tablet can compete with other ARM-based mobile devices and that giant of the tablet industry, the iPad. These devices are best suited for web-surfing, movie-watching, games and other types of content viewing, although the Surface RT's integrated keyboard gives the tablet an edge over the iPad for word processing and email composition
The Surface Pro, with its legacy app support and larger memory, is more of a productivity tablet, designed to compete with ultrabooks and the laptop market. It offers more power and can connect to existing office equipment while retaining the portability of a tablet.
This isn't a new strategy for Microsoft, which has long made a practice of offering different versions of Windows to consumers and the business world. What is new is Microsoft's decision to compete with its hardware partners by producing its own product using both ARM and x86. This reflects the computer industry's increasing awareness that consumers and businesses use different hardware to consume different content.
People want hardware that provides them with what they need, when they need it. What's powering the device is, for most people, a secondary consideration.