[OT] End-user uses for x86-64 (was: Why are still not at 64 bits)

[Jim Kuzdrall]

>   I've been asking the question, "How would an end-user significantly
> benefit from x86-64?"
>   Anyone got any other ideas?

    End users of portable processing may benefit from clock rate 
reduction.  The 64-bit internal and main memory paths double the 
processor's instruction throughput.  A given 32-bit performance can be 
had at half the clock rate in a 64-bit processor.  (Almost.  There are 
other factors.)

    The internally consumed power is proportional to the clock rate for 
CMOS technology.  Laptops and handhelds which are limited by battery 
life or heat removal may find the additional PC board area and cost 
justified.

    As For performance, the 64-bit instruction fetch from main memory 
and instruction decoder may be a bigger advantage than the 64-bit ALU.  
Main memory access time is still a big bottleneck.

   Presumably the data for video has to be continually read into cache 
from main memory, 64-bit transfers would effectively double the 
performance at the same internal clock speed.

Jim Kuzdrall