I stand corrected :)
On Thu, Dec 1, 2011 at 11:18 PM, David Ron <david.m.ron@gmail.com> wrote:
> **
>
>
> Brendan, I believe you are mistaken. Since the mid 1990's, all PCs have
> supported PAE which can address up to 36 bits, or 64 GB of RAM:
> http://en.wikipedia.org/wiki/Physical_Address_Extension
>
> The 4GB limitation is a Microsoft software limitation to get more money
> from businesses:
>
> http://www.geoffchappell.com/viewer.htm?doc=notes/windows/license/memory.htm
>
> 64GB is not unbelievably large. I work on systems with 128GB of ram
> every day (64 bit OS). My laptop has 16GB of RAM on a 32 bit OS.
>
> --David
>
>
> On 12/01/2011 12:35 AM, Brendan Kelly wrote:
> >
> > 32 bit machines support up to 4GB of RAM ONLY, not even close to 64GB of
> > RAM. 64 bit limits RAM to something unbelievably large that will likely
> > never be used (although saying that in tech is a big no no :P - cue the
> > "640K of RAM" quote hehe).
> >
> > On Thu, Dec 1, 2011 at 6:26 AM, David Ron <david.m.ron@gmail.com
> > <mailto:david.m.ron%40gmail.com>> wrote:
> >
> > > **
>
> > >
> > >
> > > Sorry... I'm going to make a few corrections....
> > >
> > > A 32 bit system has, for fear of oversimplifying, a set of 32 wires
> that
> > > wind their way through the CPU to process instructions. This means that
> > > each clock cycle can handle 32 bits of data in each clock cycle (not
> > > counting the fact that a CPU can sometimes execute more than one
> > > instruction in a cycle). A 1 Ghz processor has 1 billion clock
> > cycles in a
> > > second.
> > >
> > > In theory, A 64 bit system has 64 wires and therefore can handle
> > twice as
> > > much data in a clock cycle. In fact, this is not precisely true
> > because of
> > > the way that instructions are processed, a 64 bit system can only
> really
> > > handle less than 30% more data.
> > >
> > > There is a common misconseption that a 32-bit system can only
> > address 2^32
> > > bytes of memory which works out to 4 billion bytes, or 4gb of RAM. In
> > > truth, 32-bit systems have had support for PAE since the mid 1990s
> which
> > > allows them to support 36 bits of data, which is 2^36=64GB of RAM.
> > The 4GB
> > > limitation on 32-bit machines is an artificial limitation in Windows
> > that
> > > Microsoft has put into place to make people pay a little more for
> 64-bit
> > > support. I have 16GB of RAM in my 32bit Ubuntu installation that
> > works fine.
> > >
> > > It is true that in theory, a 64-bit machine can process data faster
> > than a
> > > 32-bit machine because there is more room to fit the instruction and
> the
> > > location in RAM that the instruction is supposed to take place
> > encoded in a
> > > single 64-bits and therefore save a clock cycle or two by doing the
> > > fetching of the data and the math on that data in a single instruction.
> > > Fortunately for us 32-bit users this is also incorrect. All CPUs have
> an
> > > instruction pipeline that can pre-fetch data before executing the
> > > instruction and so adding the extra bits really doesn't make a
> > difference.
> > > In fact, since there are more transistors in a 64-bit chip than a
> 32-bit
> > > chip, and you have to wait for all of the wires to finish before
> > moving on
> > > to the next instruction, some 64-bit chips are actually slower (in Ghz)
> > > than their 32-bit counterparts - or they can't be overclocked as much.
> > >
> > > The only place where there is more than a nominal difference in speed
> is
> > > when you are crunching extremely large integers or you need a single
> > > application to use more than 2GB of RAM. Only people who are rendering
> > > video (Pixar) or doing complex scientific calculations (NASA) would
> > notice
> > > the difference.
> > >
> > > In other words:
> > >
> > > 1. 64 bit machines aren't noticeably faster than 32 bit machines.
> > > 2. 32 bit machines support up to 64 GB of RAM
> > > 3. Microsoft has placed an artificial limitation of 4GB on 32 bit
> > windows.
> > >
> > > --David
> > >
> > >
> > > On 11/27/2011 09:27 AM, Ardell Faul wrote:
> > > >
> > > > A 32 bit system can handle 2 to the 32nd power, or 429,4967,296
> > bits of
> > > > data in each clock cycle.
> > > >
> > > > a 64 bit system can handle 2 to the 64th power, or
> > > > 18,446,744,073,709,551,616. A BIG difference.
> > > >
> > > > Ardell Faul
> > > > Computer Monitor Service Inc.
> > > > Ardell's Laptop and PC Repair
> > > > 10816 E. Mission Ave.,
> > > > Spokane Valley, Wa. 99206
> > > > ardell@icehouse.net <mailto:ardell%40icehouse.net>
> > <mailto:ardell%40icehouse.net>
> > >
> > > > 509-891-5188
> > > >
> > > > On 11/26/2011 11:07 PM, Phillip and Joyce wrote:
> > > > >
> > > > > I see some programs run on 32 or 64 bit.
> > > > > What is the differences and how can you tell what one you have?
> > > > > Phil
> > > > >
> > > > >
> > > >
> > > > [Non-text portions of this message have been removed]
> > > >
> > > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> >
> > [Non-text portions of this message have been removed]
> >
> >
>
> [Non-text portions of this message have been removed]
>
>
>
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