64-bit or Bust – Don’t Settle For Less

Casting my mind back over the last decade with regard to the development of 64-bit computing, I’ve realised that it really has taken a while for 64-bit platforms to become the mainstream. Certainly from the perspective of x86 (which is the instruction set architecture that many desktop and servers systems have used for just over thirty years), AMD got the jump on Intel and made 64-bit computing a reality for consumers back in 2003.

So why is 64-bits important?

Before I go any further, we should quickly review our byte multiple nomenclature:

• 1024 bytes = 1 kilobyte
• 1024 kilobytes = 1 megabyte
• 1024 megabytes = 1 gigabyte
• 1024 gigabytes = 1 terabyte
• 1024 terabytes = 1 petabyte
• 1024 petabytes = 1 exabyte

For most people, the real benefit lies in the extra RAM that can be addressed in 64-bit capable systems. Whilst 32-bit systems were limited to a maximum of 4GB, 64-bit systems can address up to 16 exabytes of memory although there are artificial limitations put in place at present by CPU manufacturers to cut costs. AMD, for example, limit their CPUs to 48 or 52-bit memory addressing (translating to 256 terabytes and 4 petabytes respectively).

Nonetheless, that’s still pretty huge.

As far as modern computing goes in 2010, I would not settle for a computer with less than 4GB of RAM. Having said that, my work computer has a measly 1GB which makes me and the baby Jesus cry whereas my home computer has 12GB of RAM. That aside, if you want to use the full 4GB, you need a 64-bit operating system.

Why is this so given that 32-bits can exactly address a maximum of 4GB or memory?

There is a thing called “the 3GB barrier” that can affect some computers. Without going into too much detail (and to keep things simple), some computers remap the address space typically assigned for RAM to other devices that have on-board memory – the most significant being video cards. For example, if you had a video card with 512MB of RAM and the computer had 4GB of RAM installed, you would end up with about 3.5GB RAM. The problem is made worse with larger amounts of RAM such cards.

So whilst you might think that upgrading your existing computer to the maximum 4GB under a 32-bit environment, you may not actually reap the full benefits. For the same reason, steer clear of new computers that come with a 32-bit operating system and 4GB of RAM. Whilst there have been some concerns with 64-bit computing over the years, particularly around hardware support, these issues have been largely ironed out.

As a rule of thumb, make sure your computer comes with a 64-bit operating system and at least 4GB of RAM (except for netbooks which tend to be physically limited to 2GB). RAM is cheap so there is no excuse not to get at least 4GB (or more if you can afford it).

As a final piece of advice, be wary of manufacturers that overcharge for RAM upgrades. Always check prices at a good computer shop (not Harvey Norman or Dick Smith but an actual store that specialises in computers like IT Estate or Umart) as it might be cheaper to do it yourself or enlist the services of a friendly geek (refreshing beverages or tasty food never goes astray).