Apple could use the Trusted Platform Module (TPM) chip to ensure that only Mac computers can run its OS X operating system, according to a news analysis from Gartner. 

The TPM is an open industry standard governed by the Trusted Computing Group, a non-profit organisation which develops security standards. 

The chip is used to securely store and encrypt information. Because each chip has a unique identifier code, it could also be used to distinguish a Mac computer from a model made by Dell or any other Windows vendor.

Apple revealed last week that it is to switch from IBM's Power PC architecture to Intel's x86 models. The first Intel computers are expected to be available before June 2006 and Apple's entire product line will have switched architectures by 2007, the company said at its annual World Wide Developers Conference. 

With Macs and Windows machines sharing the same hardware platform, users could theoretically install any software on the PCs, running Windows on a Mac or OS X on a Dell.

But Apple has stated that it would prevent users from installing OS X on non-Mac hardware.

An Apple spokeswoman declined to comment for this story, saying that the company it is not yet ready to reveal product specifications.

A spokeswoman for the TPG confirmed to vnunet.com that there is nothing preventing Apple from implementing the module.

Vendors of enterprise desktop and laptop computers, including Dell, HP and IBM/Lenovo, are already using the TPM. IBM, for instance, uses the chip securely to store user passwords and encrypt the contents of the hard drive. 

The upcoming Longhorn version of Windows relies on the TPM for a technology dubbed Secure Startup, which blocks access to the computer if the content of the hard drive is compromised. This prevents a laptop thief swapping out the hard drive, or booting the system from a floppy disk to circumvent security features. 

Using the TPM is not without controversy, however. The module has raised privacy concerns, and has been criticised because it could be used to enforce digital rights management technologies.

Gartner also advised enterprises to continue with purchasing plans for Apple hardware, but warned that managers should "consider delaying software purchases until vendors offer a clear roadmap for upgrades to Intel-compatible versions".

Sales of Apple computers typically drop prior to the launch of a new product as users delay purchases to get their hands on the new model.