Workshop Windows XP has been a spectacular success for Microsoft. Many companies avoided moving to Vista as it was such a big change.

Radically different hardware requirements and massive compatibility issues, coupled with a thorough overhaul of the user interface, intersected with the global economic meltdown. The end result was that most companies quite rightly concluded that XP was not fundamentally broken and carried on using it very effectively.

At the same time, PC hardware has been evolving. Multi-core chips have been available for half a decade – the end result being that much of the client PC base has the raw grunt to run Windows 7 very effectively. These chips also tend to have another, more hidden, advantage – 64-bit capability, allowing access to larger memory capacities and a new set of instructions that can make processing more efficient. Windows 7 has a native 64-bit version that can take advantage of these new features. Considering that the migration to Windows 7 is likely to be the only major upgrade for the next 4 years or so, this raises the question of whether now is the time to also consider moving to 64-bit.

From an end-user training perspective, it will make little to no difference whether the OS on their Windows 7 PC is 64 bit or not – the user experience will be virtually identical. It is the actual migration to Windows 7 that will be the hard work, not the bit count. While this may look like an argument for sticking with 32-bit, the reality is that it enables an easy migration route to 64-bit.

Windows 7, like XP before it, is likely to have a good long life. This is important when considering support for memory capacities. Windows loves memory, but 32-bit Windows struggles to support capacities above 2GB, and is limited to 4GB. With 2GB being commonly found in PCs, this may not seem like much of a problem today. But in a year or two, the relentless march of Moore’s Law will see 4GB, and more, being commonplace. At this stage, 64-bit support starts to have real relevance. Is it worth moving directly to 64-bit for all PCs to cater for this trend, or only to make the move when large memory support is needed?

Operationally, there are differences between the two versions in terms of drivers, application support and management that in the long term will mean that moving directly to 64-bit will be beneficial. However, the alternate strategy of running a mixed PC estate and then allowing 32-bit to gradually be retired is probably going to be the preferred route, especially as few individual applications demand 64-bit in order to run, and some 32-bit applications may have compatibility issues. Of course, this also means that if a 64-bit application becomes essential for the business, an upgrade of the 32-bit base will be required to support it.

Compatibility issues often arise as a barrier to the roll-out of 64-bit. This was definitely the case with early incarnations of 64-bit support with Windows XP and Vista. These problems are eased with Windows 7, as it includes a virtualised installation of XP that can be used to run 32-bit legacy applications in a compatibility mode if they do not get on with the native 32-bit support built into Windows 7.

From the management and support perspective, if you are going to be refreshing your entire desktop estate with Windows 7 then you are going to be doing a lot of testing, testing and more testing. It makes a lot of sense to take advantage of the big transition to look at 64-bit support anyhow, and whichever route you take, to supporting it as an integral and growing member of the OS fleet. And given the trends in the industry, the moment of reckoning may arrive sooner than you think.