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Was sitting in my office and someone came into talk to an admin about 32 bit vs 64 bit machines. Overheard this:
"64 bit computers are basically twice as fast as 32 bit"

Bit my lip and laughed silently.

Comments
  • 1
    But they are* :)

    * not all the time, not in all cases
  • 1
    @netikras 64bit allows HW and SW to be x-times faster than 32bit i would say... but this is a very rough reasoning

    also I don't have all the info to say what number x is and I don't want to comment bullshit and will just leave it as x
  • 0
    @netikras From user experience yes I think they are. Going from a typical 1 to 2 core 32 bit machine to a 2 to 4 core 64 bit machine will be faster if the software they are running is multicore. But the fact that it is 64 bit has little to do with any speedup. Calculations, unless they use 64 bit numbers, are not going to be any faster. And even if they do use 64 bit numbers it is not going to be twice as fast. I mainly find it amusing that people key in on a metric and make assumptions about that metric. I think the confusing part is that 64 bit machines are newer than 32 bit machines so they are by design faster. However, this has little to do with it being 64 bit.
  • 2
    @Demolishun Just a thought..

    Say you have to iterate over an array to find an index of value \x07 (say it is i=14).

    32bit:
    a. You fetch 4 bytes of that array into a registry (i.e. you make a request to DIMM to give you 4 bytes of data starting at address X)
    b. you iterate over those 4 bytes looking for something
    c. goto a

    repeat a-b 4 times (i.e. make 4 DIMM access requests)

    64 bit:
    a. You fetch 8 bytes of that array into a registry (i.e. you make a request to DIMM to give you 8 bytes of data starting at address X)
    b. you iterate over those 8 bytes looking for something
    c. goto a

    repeat a-b 2 times (i.e. make 2 DIMM access requests)

    Am I counting this wrong? The way I see it is the less DIMM access requests you make - the less latency you experience.
  • 1
    @netikras Yes, I think some parts will be faster and more efficient.
  • 0
    @Demolishun that's why there is an asterisk in my 1st comment...
  • 1
    Install Win7 32 Bit twice = Win14 64 Bit
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