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Max RAM memory

  1. Jan 29, 2009 #1
    Why, with a 32-bit adress bus , we can only have a maximum of 4 GB RAM memory?
  2. jcsd
  3. Jan 29, 2009 #2
    4GB = 2^32 bytes.

    64-bit can address 2^64 bytes.
  4. Jan 29, 2009 #3
    Thank you!
  5. Jan 30, 2009 #4
    but remember that most CPU's in todays market support Physical Address extension along with many Operating systems. All it does is extend the address bus from 32 bits to 36 bits but is still compatible with 32 bit applications and stuff. But if needed this can extend the amount of RAM from 4GB to 64GB. Thats quite the difference.
  6. Feb 17, 2009 #5
    Yeah, I believe that every bit represents a sector (usually a byte) in physical memory.
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