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  1. Desuh
    I actually am. I wonder what those questions would be.
  2. Niney
    i post in the 3ds and wii u thread sometimes but thats about it
  3. gman003-main
    Part 4:

    One last interesting thing is that 32-bit mode is itself an extension to the original x86 standard. PC processors were originally able to use only a 16-bit address space, enough for merely 64 kilobytes. This made a technique called "memory segmentation" fairly common, allowing access to about 640KB of RAM, but it was very slow and complex to use and was quickly abandoned once 32-bit processors came around.

    There are additional differences between 32-bit and 64-bit software, primarily related to how much data is processed at once (in short, more), but those are beyond the scope of memory access.

    (end transmission)
  4. gman003-main
    Part 3:

    Another point of interest is that a flat address space, where every process sees the same set of addresses, is not the only option. Processors since the Pentium Pro have supported something called "Physical Address Extensions", PAE, something that allows individual processes to "see" a different set of addresses than others.

    In practice, this means that you can give individual programs 4GB each. The programs are still 32-bit, and thus can only "see" 4GB of memory, but it does not have to be the same memory. This allows a full system to have more memory, but individual programs are still bound by that limit.

    PAE is supported in this way by most operating systems other than Windows. OS X and Linux support this. However, Microsoft claims many drivers do not work properly with it (since they need specific physical memory), and thus does not support it in 32-bit mode. I believe, however, that they use it in 64-bit mode to allow 32-bit programs to run properly.

    (continued)
  5. gman003-main
    Part 2:

    This is why 32-bit versions of Windows were often limited to 3GB of RAM, even though they can access 4GB of memory. Between the video card's memory and the dozens of small devices like temperature probes and internal connections, about a gigabyte of address space was consumed.

    A 64-bit OS can address 2 to the 64th power bytes, about 16 exabytes (16 million terabytes). That's probably going to be more than enough for anybody, at least for the foreseeable future.

    However, modern processors are often physically limited below this. Early 64-bit processors only supported 36 bits of actual address space. This has gradually increased - cheap processors now provide 40 bits, and server-grade processors often have 48 bits. This is mainly because of cost - 48 bits is enough for 256 terabytes of address space, but increases the price of the memory controller and other parts. But the software is compatible with any of these - you do not need a "48-bit" OS.

    (continued)
  6. gman003-main
    An excellent question:

    A 32-bit operating system, using a flat address space, can access 2 to the power of 32 bytes. That is because it uses 32-bit integers to give an address to each byte, so that it may be access. For analogy, consider road addresses - if you only have space for four numbers and a street name, you could only have 10,000 buildings on one road before you run out of numbers.

    One point of interest is that this is the address space. Computers do not give addresses to just RAM, but to other things as well. A video card, particularly one with a lot of VRAM, can use a few gigabytes of address space (since all of that memory can be used by the processor). Other devices, like SATA controllers, use far less space than they may provide access to, because storage devices (like hard drives) are not directly accessible to the processor.

    (continued)
  7. gman003-main
    You have reached the GMan003 Computer Fact Hotline. Do you have any specific requests for computer facts, or is this a nonspecific call for computer facts?
  8. Alrækinn
    No, it's from a manga called Oyasumi Punpun, it's how they depict god in it.
  9. Alrækinn
    [img]http://puu.sh/32sz7[/img]
  10. cccritical
    I met a guy from zimbabwe once, he was incredibly chill

    also he only called it 'zimbabwe' once and referred to it as 'zim' from there on, so now every single time I think of it I think of it and speak of it as 'zim' and others look at me confusedly
About Samiam22

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