Newer Pentium 4s
EMT64T was Intel’s implementation of AMD’s AMD64 architecture. It is essentially a straight-forward copy of AMD’s strategy of making 64-bit extensions to the 486 architecture. The creation of EM64T has as much to do with company politics as it does to do with technology. Unlike AMD, Intel had always maintained that 64-bit functionality was unnecessary in today’s computing climate. AMD, on the other hand, has long been firmly entrenched in the 64-bit mindset. Hence, the development of EM64T, which essentially copied AMD’s architecture, could be construed as an admission that AMD was right all along. Because of this, EM64T chips were released with little fanfare. In fact, most people buying the first EM64T chips would have been unaware that their chips were 64-bit capable.
EM64T was first featured on Intel’s Xeon processor, which was in itself an answer to AMD’s Opteron processor. It is also present on newer Pentium 4s. It is not planned to be released on any laptop processor for another year. It is almost fully compatible with AMD64, and Intel has said that it will be completely compatible by the end of the year.
Intel looks upon the EM64T architecture as a form of “future-proofing”. They acknowledge that most setups will not currently use the technology, but they state that when 64-bit software becomes more mainstream (which they expect to be within the 3-year lifecycle of a new computer), their processors will support it.
EMT64T competes directly with AMD64’s market, in both the home desktop, business desktop (in the form of P4) and enterprise and server market (in the form of Xeon).