Hands on: Embrace the spirit of 64-bit

PC enthusiasts have long understood the benefits of upgrading their Ram for better performance.

The difference between systems upgraded from 512MB to 1GB of Ram, for example, can be staggering, but what about the jump from 2GB to 4GB of Ram?

Previous experience of doubling system memory would imply further benefits, but upgrading to 4GB of Ram can be a grey area to say the least.

First, you’ll need hardware which can physically accommodate and recognise 4GB of Ram. You can check specifications at the manufacturer’s website.

The chipset will be a limiting factor, as well as the number of physical memory card slots available.

Operating system
Your hardware may support 4GB or more, but the OS may not know what to do with it. 32-bit operating systems may address up to 4GB of memory, but that doesn’t mean you’ll necessarily get to use it all.

Various devices, such as graphics cards, require memory-mapped access, and this must be contained within the 4GB addressable limit on a 32-bit OS.

Microsoft warns that some systems could end up having less than 3GB remaining, but the maximum available to 32-bit versions of Vista will only ever be around 3.12GB. If your processor supports technologies like Intel’s PAE though, you may be able to maximise the amount of Ram.

If you want to use all 4GB of Ram, you’ll need a 64-bit operating system and a processor that understands a 64-bit instruction set. Luckily, both AMD and Intel CPUs have supported 64-bit extensions to the x86 instruction set for some time now, and Windows Vista is available in 64-bit versions.

To see how a 4GB upgrade works we took an existing PC equipped with 2GB of Ram, using a pair of 1GB Crucial DDR-II memory cards. The Asus motherboard has four memory card slots and ­ according to both Asus and the Crucial Memory Advisor Tool ­ its Intel 975X chipset and physical design supports 8GB of Ram.