Paul Otellini, CEO of long-time Microsoft partner Intel, is miffed about Microsoft using ARM-based processors in tablets for the upcoming Windows RT operating system. And he's talking smack about it.\n\tAt Intel's annual investor meeting yesterday, Otellini did his best to paint ARM-based Windows tablets as dangerously incompatible with legacy Windows apps and that x86 chips developed by Intel will support applications written for previous versions of Windows.\n\t"I think they have a big uphill fight," Otellini was quoted as saying of the ARM-based competition in a blog post on The Verge.\n\t"We have the advantage of the incumbency, advantage of the legacy support. Not just in terms of applications but devices."\n\tClearly, a civil war is brewing between Intel and Microsoft, and it started when Microsoft decided to port Windows to ARM-based chips in anticipation of the release of Windows RT (formally called Windows on ARM), the cousin to Windows 8 that will run on most tablets.\n\tFor Microsoft, Windows RT on ARM is its best hope to make any progress in the tablet market against the mighty iPad and other Android-based tablets like the Kindle Fire. All tablets use ARM-based chips because they enable low power consumption and long battery life.\n\n\tNavigating Windows 8: A Visual Tour\n\tDesire for Windows 8 Tablet Shrinking, Forrester Says\n\n\tMicrosoft has come clean that Windows RT tablets will not be able to run or port existing x86 applications. It's probably in Microsoft's best interest to keep making this point abundantly clear so Windows RT users don't cry foul when legacy apps and devices don't work with their shiny new tablets.\n\tWith his comments calling out Microsoft for going ARM, Otellini is openly protecting his x86 turf. It's no secret that Intel has to worry about customers migrating off traditional PCs running x86 architecture to light and fast ARM-based tablets.\n\tIntel has reacted to this threat by developing a new low-power Atom chip which will be used in Windows 8 (not Windows RT) tablets using Intel chips. But can an X86-based chip, even a low power one like Atom, compete with ARM, the king of all tablet chips?\n\tOne thing's for sure: Consumers don't give a hoot about legacy apps. But CIOs and IT execs do. Though Windows RT app compatibility is probably not as big a deal as Otellini thinks, he does have a point about the importance of app compatibility across devices in the enterprise.\n\tWhat do you think? Will Windows RT ARM-based devices be handicapped by app incompatibility?