Microsoft Windows 7 : 32-bit or 64-bit?

More and more computer manufacturers like Dell or HP are offering the 64-bit version of Windows 7 by default even on devices that are destined for home and small business users often with no clear downgrade path.

This article will look at the various implications of moving from a 32-bit platform to a 64-bit one and offers some insight into how common issues like compatibility and legacy can be addressed.

64-bit Microsoft operating systems have been around ever since Windows XP (i.e. for more than a decade now) but it is only with Windows 7 that the trend to move away from 32-bit to 64-bit has picked up.

According to Steam, the popular games distribution network, the Windows 7 64-bit has the fastest growing marketshare in the operating system category and is second only to Windows XP 32-bit, a result that is heavily skewed but which gives a general picture of the shift taking place.

So why choose 64-bit over 32-bit? Well, the single most important reason has to do with memory management. 32-bit operating system can manage up to 3.3GB of memory and with entry level laptops sporting 4GB RAM, it's only a matter of years before 32-bit OSes are relegated to the lowest rung of the PC ladder.

Then there's the interesting benefit of enhanced security due to hardware-backed DEP, Kernel Patch Protection and compulsory driver signing (which reduces random crashes).

But choosing 64-bit rather than 32-bit Windows 7 comes with its own sets of caveats; firstly, old software might not work and old hardware will almost always fail to work.

This means that some may have to upgrade their existing hardware (like old scanners and tape backup devices) and software. For the latter, things can become trickier especially for 16-bit applications that are still being used (ed: you might want to use DOSBox) and some antivirus applications.

Some have also reported that 64-bit operating systems can consume an extra 350MB worth of RAM compared to their 32-bit counterpart, which is fair enough if moving to 64-bit allows you to recover an extra 500MB memory.

Furthermore, most of today's software have been written and optimised for a 32-bit environment and moving to 64-bit might actually cause applications to run slower because of additional resources needed by the system.

But this is changing rapidly and native 64-bit versions of many popular applications have already been released. Microsoft has provided users with a compatibility centre that helps identify which applications could be problematic.

To make matters more complicated, you cannot upgrade from 32-bit to 64-bit or vice versa. You will have to back up your files and do a complete installation and you won't be able to run 64-bit applications on 32-bit operating systems if ever you have a change of heart.

That's fine when you've got dual-platform applications like Microsoft Office 2010 but we've seen a couple of developers that actually require that you buy 32-bit or 64-bit versions separately. Indeed, even Microsoft sells separate 32-bit and 64-bit versions of Windows 7.

Ultimately, it all boils down to your current situation. If you've got a new computer, with plenty of memory and no old hardware and software, then go for it, otherwise, it would be wise for you to test it beforehand.