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  • Dual Core CPUs

    Forgive my ignorance, I understand the new 64 bit CPUs should work on 32 bit and presumably 16 and 8 bit software, just as the previous 32 bit CPUs ran 16 and 8 bit software. But my server Orange quotes their new Vista CD installation disk for their speedtouch modem will only work with 32 bit CPUs, so presumably I dare not buy a 64 bit CPU with Vista until they claim it is compatible.

    Also if you have a dual core CPU how do you change it over from 32 to 64 bit etc. I presume it could only be achieved by the cumbersome method of accessing the CMOS setup after bootup.

    Gordon

  • #2
    Re: Dual Core CPUs

    (Orange from all I have read is a rubbish ISP. There is even a forum dedicated to complaints about Orange, UK hosted of course.)

    I think what Orange may be babbling about is if you use the USB connection on the Speedtouch (which requires a driver). I think one of them only had a USB connector so you weren't able to use the usual Ethernet option on most modems. I would advise getting a better modem, one that has an Ethernet connection.

    The way to change a Dual Core from 32 bit to 64 bit, is to buy a 64 bit Dual Core CPU and have a 64 bit motherboard to install it in. If you already have a 64 bit Dual Core CPU, then you need to install a 64 bit version of the operating system.
    1 1 was a racehorse.
    2 2 was 1 2.
    1 1 1 1 race 1 day,
    2 2 1 1 2

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    • #3
      Re: Dual Core CPUs

      Thanks for the help B. Yes a lot have left Orange because of the poor service, I wonder if you know the address of the site dealing with loads of complaints. I would also have left Orange a long time ago except they host 5 Free sites I manage the main one being below. Also I do get a lot of pleasure using their Seniors Forum and run a little daily news page with the help of contributions from members.

      So I take it even if you do have a dual core CPU you can only use it either as a 32 o 64 bit CPU depending on the type of Motherboard.

      Gordon

      http://sionet.mysite.wanadoo-members.co.uk

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      • #4
        Re: Dual Core CPUs

        Realize I'm over here in Italy which is often a technology "Dark side of the moon" but as I recall (and I have a 64-bit capable dual core Intel 945 (not a core duo), here's how this works:

        We have the 64 bit Itanium -- runs only a 64 bit OS

        We have AMD that pioneered the 32 bit processor w/ 64 bit extensions (AMD64)

        We have Intel jumping on the AMD64 (rebranded as EM64T) bandwagon.

        EM64T proves far more cost effective than Itanium.

        EM64T is a 32 bit processor when running a 32 bit OS.

        EM64T is a 64 bit processor still capable of running 32 bit applications without emulation when running a 64 bit EM64T capable OS.

        Dual and quad core processors have nothing in particular to do w/ 32 bit vs. 64 bit other than they were created after the broad acceptance of EM64T.

        EM64T processors require compatible chipsets (N/S bridge) that support "all" processor features.

        Unless other chipset manufacturers are vastly different than Intel, you do not need a different motherboard to support 64 bit. One compatible w/ the EM64T capable processor will support both a 32 and 64 bit OS.

        Please correct my lack of understanding a year over here may have caused.
        Last edited by rvalstar; 29th May 2007, 22:55. Reason: typo; AMD64 vs. EM64T correction
        Cheers,

        Rick

        ** Remember to give credit where credit is due and leave reputation points sigpic where appropriate **

        © 2006-2099 R Valstar. This post is offered "as is" for discussion purposes only with no express or implied warranty of any kind including, but not limited to, correctness or fitness for use. Nothing herein shall be construed as advice. Attempting any activity based on information in this post is done at your own risk.

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        • #5
          Re: Dual Core CPUs

          One more thing; an Intel "Dual Core" CPU is either 32 bit OR it is 64 bit. You cannot switch it between two "modes". If it's a 32 bit CPU with two cores, then such it is, and will only run 32 bit operating system and software. If it's a 64 bit dual core CPU, then it's a 64 bit CPU with two cores and will only run a 64 bit OS.

          I'm not sure about software; can I presume that a 32-bit version of your Desktop Productivity Software (Word, Excel, Corel!Draw, OpenOffice) will run under a 64 bit OS on a 64 bit CPU? Someone will know...


          Tom
          For my own and your protection, I do not provide support by private message under any circumstances. All such messages will be deleted and ignored.

          Anything you say will be misquoted and used against you

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          • #6
            Re: Dual Core CPUs

            Originally posted by Stonelaughter View Post
            One more thing; an Intel "Dual Core" CPU is either 32 bit OR it is 64 bit. You cannot switch it between two "modes". If it's a 32 bit CPU with two cores, then such it is, and will only run 32 bit operating system and software. If it's a 64 bit dual core CPU, then it's a 64 bit CPU with two cores and will only run a 64 bit OS.

            I'm not sure about software; can I presume that a 32-bit version of your Desktop Productivity Software (Word, Excel, Corel!Draw, OpenOffice) will run under a 64 bit OS on a 64 bit CPU? Someone will know...
            Not at all. My 945 "Dual Core" will run either a 32 bit or 64 bit OS and I have run both with success.

            And per

            http://www.intel.com/technology/intel64/index.htm

            The new Core Duo's are also EM64T based and are capable of running both 32 and 64 bit OSs:

            Intel 64 architecture represents a natural addition to Intel's computing architectures, allowing platforms to access larger amounts of memory. Processors with Intel 64 architecture support 64-bit-capable operating systems from Microsoft, Red Hat and SuSE. And processors running in legacy mode remain fully compatible with today's existing 32-bit applications and operating systems.
            And yet more info from:

            http://www.redbooks.ibm.com/Redbooks...0475.html?Open

            Note I mis-stated AMD's initial technology as EM64T when it is AMD64

            There are now three 64-bit implementations in the “Intel® compatible processor” marketplace:

            Intel IA64, as implemented on the Itanium 2 processor
            Intel EM64T, as implemented on the Xeon DP “Nocona” and future Xeon MP processors
            AMD AMD64, as implemented on the Opteron processor

            There is some uncertainty as to what a 64-bit processor is and even more importantly, what the benefit of 64-bit computing is. This document introduces the EM64T and AMD64 architectures and explains where 64-bit processing is useful and relevant for customers in this marketplace.
            .
            Contents
            _
            A 64-bit processor is a processor that is able to address 64-bits of virtual address space. A 64-bit processor can store data in 64-bit format and perform arithmetic operations on 64-bit operands. In addition, a 64-bit processor has general purpose registers (GPRs), and arithmetic logical units (ALUs) that are 64-bit wide.

            The Itanium 2 has both 64-bit addressability and GPRs and 64-bit ALUs, so it is by this definition a 64-bit processor.

            The discussion whether or not EM64T and AMD64 really are 64-bit processors can be confusing to some because Intel calls its architecture “Extended Memory 64 Technology”. We know that it extends the IA32 instruction set. Therefore, are EM64T and AMD64 processors “real” 64-bit chips? The answer is absolutely yes. When these processors operate in 64-bit mode, the addresses are 64-bit, the GPRs are 64 bits wide, and the ALUs are able to process data in 64-bit chunks. Therefore, these processors are full-fledged 64-bit processors in this mode.

            Note that while IA64, EM64T, and AMD64 are all 64-bit, they are not compatible:
            EM64T and AMD64 are, with the exception of a few instructions such as 3DNOW, binary compatible with each other. Applications written and compiled for one will usually run at full speed on the other.
            IA64 uses a completely different instruction set to the other two. 64-bit applications written for the Itanium 2 will not run on the EM64T or AMD64 processors, and vice versa.

            There are three distinct operation modes available in AMD64 and EM64T:

            32-bit legacy mode

            The first and, in the near future, probably most widely used mode will be 32-bit legacy mode. In this mode, both AMD64 and EM64T processors will act just like any other IA32 compatible processor. You can install your 32-bit OS on such a system and run 32-bit applications, however, you will not be able to make use of the new features such as the flat memory addressing above 4 GB or the additional General Purpose Registers (GPRs). 32-bit applications will run just as fast as they would on any current 32-bit processor.

            Most of the time IA32 applications will run even faster since there are numerous other improvements that boost performance regardless of the maximum address size. For applications that share large amounts of data, there might be performance impacts related to the NUMA-like architecture of multi-processor Opteron configurations, since remote memory access might slow your application down.

            Compatibility mode

            The second mode supported by the AMD64 and EM64T is compatibility mode, which is an intermediate mode of the full 64-bit mode described below. In order to run in compatibility mode, you will need to install a 64-bit operating system and 64-bit drivers. If a 64-bit OS and drivers are installed, both Opteron and Xeon processors will be enabled to support a 64-bit operating system with both 32-bit applications or 64-bit applications.

            Compatibility mode gives you the ability to run a 64-bit operating system while still being able to run unmodified 32-bit applications. Each 32-bit application will still be limited to a maximum of 4 GB of physical memory. However, the 4 GB limit is now imposed on a per-process level, not at a system-wide level. This means that every 32-bit process on this system gets its very own 4 GB of physical memory space (assuming sufficient physical memory is installed). This is already a huge improvement compared to IA32, where the operating system kernel and the application have to share 4 GB of physical memory.

            Additionally, compatibility mode does not support the virtual 8086 mode, so real-mode legacy applications are not supported. 16-bit protected mode applications are, however, supported.

            Full 64-bit mode

            The final mode is the full 64-bit mode. AMD refers to this as long mode and Intel refer to it as IA-32e mode. This mode is when a 64-bit operating system and 64-bit application are used. In the full 64-bit operating mode, an application can have a virtual address space of up to 40-bits (that equates to 1 TB of addressable memory). The amount of physical memory will be determined by how many DIMM slots the server has and the maximum DIMM capacity supported and available at the time.

            Applications that run in full 64-bit mode will get access to the full physical memory range (depending on the operating system), and will also get access to the new GPRs as well as to the expanded GPRs. However it is important to understand that this mode of operation requires not only a 64-bit operating system (and of course 64-bit drivers), but also requires a 64-bit application that has been recompiled to take full advantage of the various enhancements of the 64-bit addressing architecture.
            Last edited by rvalstar; 29th May 2007, 22:53. Reason: more info
            Cheers,

            Rick

            ** Remember to give credit where credit is due and leave reputation points sigpic where appropriate **

            © 2006-2099 R Valstar. This post is offered "as is" for discussion purposes only with no express or implied warranty of any kind including, but not limited to, correctness or fitness for use. Nothing herein shall be construed as advice. Attempting any activity based on information in this post is done at your own risk.

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            • #7
              Re: Dual Core CPUs

              Hmmmm.... *now thoroughly confused*


              Tom
              For my own and your protection, I do not provide support by private message under any circumstances. All such messages will be deleted and ignored.

              Anything you say will be misquoted and used against you

              Comment


              • #8
                Re: Dual Core CPUs

                Don't know why this is confusing.

                This was AMD's big leg up on Intel (for a few months) and effectively killed the Itanium from widespread use. Make a backwards compatible processor w/ a bunch of extra instructions and wider registers such that SW can take advantage of the new stuff and the old stuff can run too. Not the best design but the best approach for the market.

                Remember the 8088? Something between an 8 and 16 bit processor w/ a 20 bit address space and screwy memory segmentation? It was instruction compatible w/ the 8080 such that you could run DOS 1.0 OR CP/M -- that was the goal at least. Intel killed Zilog and the Z80 in the process and kept Motorola in check w/ their far superior 68000 line.

                Do buy the Itanium and help out all my HP stock (eventhough the gang was traded to Intel). Truely a far superior chip (like Motorola's 68000 was as compared to the 8088 ) but at too high a price point for the market.
                Cheers,

                Rick

                ** Remember to give credit where credit is due and leave reputation points sigpic where appropriate **

                © 2006-2099 R Valstar. This post is offered "as is" for discussion purposes only with no express or implied warranty of any kind including, but not limited to, correctness or fitness for use. Nothing herein shall be construed as advice. Attempting any activity based on information in this post is done at your own risk.

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                • #9
                  Re: Dual Core CPUs

                  Hi everyone.

                  I have the following setup:

                  Dell Dimension 5150 (Pentium D @ 2.8 GHz with EM64T) running Ubuntu.
                  Inside Ubuntu, I am running VMware Server with Windows Server 2003.

                  We got a new computer that is a bit better (Dell Dimension E520 - Pentium D @ 3 GHz, cache is twice the size, faster memory, etc, and also EM64T).

                  I was planning to install Ubuntu on the new system, and moving the virtual machine.
                  When I was comparing both system's specs, I realized they both have EM64T. I didn't know that.
                  Then I realized I am running 32 bit OSs (both Ubuntu and Windows Server) on 64 bit capable systems.

                  So the question is, is it worth it reinstalling everything?
                  Is a system slower because of running a 32 bit OS, or just not taking advantage of the larger memory addressability (which I won't use soon)?

                  What if I install 64bit Ubuntu and keep running 32bit virtual machine?

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