Hardware anti-virus measures, known as Execution Protection by chip maker AMD, will soon be used in processors to stop the running of virus routines such as buffer overflows, with no more than a reboot being required to remove the offending code.
The new Athlon 64 chips, already in production by AMD, have this capability built-in, but has yet to be activated. Microsoft's Service Pack 2 for Windows XP will make it functional and will be released early Q2 this year.
The processor will work as a reader, rather than an executor, so no memory overflow will be produced. Intels new Pentium 4 chip, called the Prescott, will have similar technology embodied into it. Source