One question I get asked more and more frequently when helping someone choose a new laptop is: Should I go for 32Bit or 64Bit Windows? Well, the answer isn't so straight forward.

The 32 or 64 bit architecture refers to the memory address length that can be referenced by the processor. This also has an impact on the maximum amount of memory that can be utilised, which is 4GB for a 32 bit CPU (but in reality the maximum accessible ram is anything from 3GB to 3.5GB depending on other hardware allocations such as the graphics card).

Having a 64 bit OS doesn’t automatically make all applications faster because much of today’s software is written and optimised for a 32 bit era. You’ll need software specifically optimised for 64 bit processing to take advantage of any speed improvements. Until recently the only major software package (that is 64Bit) of note was Adobe CS4, but more are being released, such as Internet Explorer 64Bit, Firefox 64Bit and iTunes 64Bit.

In the not too distant future, 64Bit computing will be a common standard – as all hardware from the last couple of years has been designed with this in mind. Until a complete upgrade cycle has passed for the majority of users, there is still a case for some users to stick with 32 bit Windows for the time being.

A few things you may not know:

• You can address much more than 4GB of memory, which is ideal for avid gamers, CAD, video editors and heavy multi-taskers. However, any 32 bit software you use will still be restricted to 4GB memory – you need a 64 bit CPU, OS and applications to take full advantage of the extra RAM.
• Existing 32 bit drivers & Unsigned kernel-mode drivers no longer work.If you have older or poorly supported hardware you may find that it can no longer be used. Got a 7 year old scanner that just about works in Vista? You may not be able to get it working in 64 bit Windows 7.
• Running some 32 bit applications on a 64 bit OS could actually be slower. The additional overheads in running 32Bit software in 64Bit mode could cause a slight degradation in performance, around 10-20%. It will take some time for 64Bit software to become the norm.