How much RAM can your 64-bit CPU address?

Your old 32-bit CPU, could address up to 2^32 memory addresses, that’s 4294967296 different memory addresses, better said, “only” 4GB, something that 15 to 20 years ago was 1000 larger than any memory created at the time.

Now we have 64-bit CPUs, that means they can address up to 2^64, that’s 18446744073709551616 different memory addresses, better said, 16.8 million terabytes which is the same as 16 exabytes, which as of now (May 2008), represents way more than the total RAM ever created for all computers summed together.

Let’s see if in 20 years, 16 exabytes will be enough, I personally don’t think so, it never is, we always laugh at the tech limitations of the past, in no time we’ll end up with 128-bit processors and I’ll leave you the homework to find out how much memory those CPUs will be able to address.

4 Comments

  1. Wow, I find it hard to understand how 16 exabytes won’t be enough in 20 years. I find it real hard.

    Imagine what kind of hardware/software will be using that amount of memory, the first series of Terminators? xDD

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