no, 32 bit hardware can only support 4GB of RAM. It's not physically
possible for it to support more. 2^32 is 4294967296 ... that's how many
bytes a 32 bit machine can address. 64 bit machines can address
1.844674407×10¹⁹ bytes of RAM. It has nothing to do with microsoft putting
in a limitation, it's a physical limitation of the hardware.
On Thu, Dec 1, 2011 at 11:10 PM, David Ron <david.m.ron@gmail.com> wrote:
> **
>
>
> You're not wrong, I thought that I made that clear in my message. But I
> was trying to correct a few misconceptions:
>
> 1. 32 bit systems can process 2^32 bits of data in a clock cycle. This
> is incorrect. A 32 bit system processes 32 bits in a clock cycle
> (give or take for pipelining, prefetch, hyperthreading, PAE and
> other efficiencies).
> 2. 32 bit systems are faster. This is incorrect.
> 3. 32 bit systems can only address 4gb of ram. This is ONLY correct in
> Windows not because of a hardware limitation rather because of an
> artificial limitation in place by Microsoft.
>
> --David
>
>
> On 11/30/2011 10:06 PM, RogerX19 wrote:
> >
> > David,
> >
> > Correct me if I'm wrong, but I think you are talking about 32 bit vs.
> > 64 bit processors (that is, hardware)
> >
> > I believe Phil was referring to 32 bit vs. 64 bit Windows.
> >
> > Not to say that you are wrong, but I think we need to clarify which we
> > are talking about.
> >
> > As example, your statement "32 bit machines support up to 64 GB of RAM
> > "... may be true (I don't know), but this 32 bit Windows I'm running
> > only supports 3+ GB.
> >
> > It's the difference between 32/64 bit processors and 32/64 bit
> > software, and for the benefit of those who don't recognize the
> > difference, perhaps we should be state of which we speak?
> >
> > rogerX
> >
> > --- In simplycomputers2@yahoogroups.com
> > <mailto:simplycomputers2%40yahoogroups.com>, David Ron
> > <david.m.ron@...> 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@... <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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