There is still difference between EM64T (Intel's x86-64 implementation) and AMD64. EM64T was derived from the long-time undisclosed project, codenamed as Yamhill. From sources I have read (x-bit labs? could not remember), Intel actually reverse-engineered AMD's CPU and AMD's early-openly development documents to get Yamhill to work. But in AMD's document, AMD made a mistake of leaving one instruction out of documents. However, Intel followed this mistake. So EM64T lacks one instruction that AMD64 has. But since this instruction is almost for internal use, such difference is not critical. Why there is no yet another case? AMD did reverse-engineering before to 386, 486 and Pentium before (AMD and Intel had filed case for this). And they two are all messed with numerous cross-license after so many years' R&D, manufacture and acquisition. So any case is just wasting and results in lose-lose case. I just felt shame for Intel the whhole process of rolling out EM64T. Hope both of them can be honest. As consumer, let us enjoy more price-cutting.
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There is still difference between EM64T (Intel's x86-64 implementation) and AMD64. EM64T was derived from the long-time undisclosed project, codenamed as Yamhill. From sources I have read (x-bit labs? could not remember), Intel actually reverse-engineered AMD's CPU and AMD's early-openly development documents to get Yamhill to work. But in AMD's document, AMD made a mistake of leaving one instruction out of documents. However, Intel followed this mistake. So EM64T lacks one instruction that AMD64 has. But since this instruction is almost for internal use, such difference is not critical.
Why there is no yet another case?
AMD did reverse-engineering before to 386, 486 and Pentium before (AMD and Intel had filed case for this). And they two are all messed with numerous cross-license after so many years' R&D, manufacture and acquisition. So any case is just wasting and results in lose-lose case.
I just felt shame for Intel the whhole process of rolling out EM64T. Hope both of them can be honest. As consumer, let us enjoy more price-cutting.