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  1. Old Comment

    Un-met Expectations -- a real example

    There is another skid mark on this topic. That is the issue of 32-bit vs. 64-bit vs. physical memory. As I understand things, 4 Gbytes of ram is 2**32 bytes. In contrast a 32-bit address space can access 2**32-1 bytes -- one less -- physical bytes. Therefore, a 32-bit distro release requires the physical address extension (PAE) kernel package to access all of the 4 Gbytes of physical ram. This applies not only to the running kernel but also
    to the boot loader. A 64-bit distro release does not have these limits. Your mileage may vary.
    Not exactly. 4 Gbytes of ram is 2**32 bytes and a 32-bit address space can access exactly 2**32 bytes (0 through 2**32-1 bytes inclusive). BUT, the motherboard BIOS will want some of that 32-bit address space (typically the last gigabyte) for its hardware, leaving only 3 Gbytes or so for actual addressable ram in the 32-bit address space. Any ram beyond that amount, the motherboard will bump up beyond the 32-bit address space. Therefore, if you have 4 Gbytes of physical ram, you will need to use PAE in the kernel in order to be able to see all 4 Gbytes of ram. Otherwise, you will only see the 3 Gbytes or so that the motherboard allows in the 32-bit address space. PAE is clever hand waving in the microprocessor paging module that essentially allows the microprocessor to generate a 36-bit address (64 Gbytes addressable) from the 32-bit address it is given. A 64-bit distro release does not have these limits, since it uses long mode in the microprocessor chip and that uses a 64-bit address space (17179869184 Gbytes addressable).
    Posted 08-04-2014 at 03:08 AM by xode xode is offline
  2. Old Comment
    Posted 10-11-2012 at 03:49 AM by brianL brianL is offline
  3. Old Comment

    My Choice of Avatar -- The Sorcerer's Apprentice

    hey there saint i too have a thinkpad tablet trying to convert to linux any help would be an absolute godsend as i have no transport untill i finish conversion as tablet will be running the auto tune function in my car to make it run and as a media player for my sounds yours sincerely loopsta!
    Posted 10-09-2012 at 09:57 PM by loopsta loopsta is offline
  4. Old Comment

    My Choice of Avatar -- The Sorcerer's Apprentice

    By the way, I failed to give due credit. The Sorcerer's Apprentice was a Disney character in the original Fantasia film (1940). The experience was so special that it was repeated in Disney's the second Fantasia (2000) film.

    The character, Sorcerer's Apprentice, was made into its own feature film released in 2010.

    All rights belong to the respective trademark and copyright holders. I'm a fan along for the ride.

    ~~~ 0;-Dan
    Posted 09-29-2010 at 10:57 AM by SaintDanBert SaintDanBert is offline


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