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Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

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On 20 Nov 2018 09:16, Thomas 'PointedEars' Lahn wrote:
>Sergio wrote on 20.11.2018 04:57:
>>    64 bit ? means 64 bit wide accumulator
>No, primarily it means a 64 bit wide *address* *bus*.

Only sort of.

In the old days when the natural data unit size and the address bus size
were often different, "xx bits" meant the natural data unit (accumulator,
if relevant) size.  The address bus width was often different.
DEC in its earlier days had 12, 18, 16, 36 and 32 bit systems before its
64 bit Alpha. The 16 bit PDP-11 had 16, 18 or 22 bits of address space,
depending on the model.

These days, both the natural unit and (theoretical) address bus size
are the same, and the same instructions could manipulate both.
Physical and virtual memory blur things more.

64 bit processors treat address pointers as 64 bit values BUT:

These days, *no* "64 bit" processor can address a full 64 bits of memory,
physical or virtual. Depending on processor, some address lines will 
either be nonfunctional or cause a nonexistent memory fault if set.
A full 64 bits of memory would be over 18 exabytes of memory.
The latest x86-64 can theoretically address 56 bits worth of virtual 
memory, at least internally.

>>Shut up as you do not know what you are talking about.

>And stop amok-crossposting.

>Fup2 poster

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What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-15 17:17 +0000
  Re:What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-11-15 19:54 +0100
    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-15 20:32 +0100
      Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Shon Wible <shwn@shouve.wd> - 2018-11-16 20:22 +0000
      Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-19 17:26 -0600
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Lochù Umská <lare@cpi2alwa.cc> - 2018-11-19 23:35 +0000
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-19 22:05 -0600
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Elden Lathan <an@tnettw.ea> - 2018-11-22 19:25 +0000
        Gravitational waves (was: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-20 03:11 +0100
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-19 22:23 -0600
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< benj <benj.fake@gmail.com> - 2018-11-20 11:46 -0500
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-20 21:26 +0100
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-20 15:51 -0600
            Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Paul Edgar <lara@uldewan.lg> - 2018-11-21 18:12 +0000
              Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-21 13:43 -0600
    Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-15 20:54 +0000
      Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-19 21:57 -0600
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-20 09:16 +0100
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-11-20 17:48 +0000
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Keith Stein <keithstein111@gmail.com> - 2018-11-20 12:47 +0000
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-20 10:01 -0600
      Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Edward Prochak <edprochak@gmail.com> - 2018-11-20 08:22 -0800
        Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< benj <benj.fake@gmail.com> - 2018-11-20 12:10 -0500
          Re: What Every Physicist Needs to Know..............<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Sergio <invalid@invalid.com> - 2018-11-21 13:50 -0600

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