Silicon Insider heeft een uitgebreid artikel in elkaar gezet van AMD K8 processor, codenamed Sledgehammer. Hieronder vast een klein stukkie, lees hier verder.
In his presentation at Microprocessor Forum, Fred Weber (VP of engineering, in AMD's Computational Products Group) made it quite clear that AMD intends to take on existing high end RISC processors and Intel's new IA-64 product line with x86-64. They have addressed the two biggest disadvantages the current x86 ISA has - lack of 64-bit addressing, and disadvantageous floating point performance architecture. Through conveniently selective comparisons he tried to show that AMD's K7 family had caught up to the fastest RISCs in integer performance. Mr. Weber claimed that the new architecture will allow future AMD processors to close the gap in floating performance.
Apparently the extension to 64 bits will come without too much pain either. AMD claims that stretching 32 bit x86 to x86-64 only adds 5% to processor die size, and since the same processor core executes 32 and 64-bit code the performance will be equivalent. This might be a bit of a stretch since research conducted at DEC indicates that in practice compiling an application with 64-bit addressing instead of 32-bit addressing causes a performance loss of about a 4 - 5% on average. This results from address data taking up more room in the data cache and main memory causing the cache and TLB miss rates to increase.