Q: I hear there is some sort of memory limitation with Vista. Can you explain that?

– Submitted by many

A: Without getting too technical, 32-bit versions of Windows Vista have a hard limit of 4 GB of RAM, but due to technical reasons may only be able to use 2.5 to 3.5 GB of RAM. This means that even if you fill your computer with 4 GB of RAM or more, you will only be able to use between 2.5 and 3.5 depending on your computer. 64-bit versions of Vista can fully address from 8 GB to 128 GB of RAM, so in practice 64-bit Vista does not suffer from “the Vista memory limitation”. It would then seem that users should simply make sure they are purchasing a 64-bit versions of Vista to avoid memory limitations. However, it may not always be that simple.

A little background first on the Vista memory limitation. The 4 GB limitation is not unique to Vista. Windows XP and other 32-bit operating systems also have a 4 GB limit (FYI – there is a 64-bit version of Windows XP as well, but its use is very limited). This limit was never really an issue for most users as 4 GB was an extraordinary amount of RAM up until recently. Even today, 4 GB of RAM is a large amount of RAM, but it is no longer an unusual amount. The large memory demands of Vista can make 4 GB of RAM or more a realistic requirement for many power-users. So with the advent of Vista, the 2.5 to 3.5 GB memory limitation has suddenly became a problem for many more users than before. And while today it may only be a problem for power-users, history has shown that memory requirements for Windows operating systems grow steadily year to year. So it will likely become a much larger issue over the next couple of years.

So why can’t users simply purchase the 64-bit version of Vista and be done with the memory limitation? For many users 64-bit Vista may be a feasible solution. However, most computer purchasers have no idea that there is a memory limitation, much less the difference between 32 and 64-bit versions. Certainly, most big-box retail stores do not offer choices between 32 and 64-bit, nor would the sales associates necessarily even understand the technical differences. So many users are purchasing Vista computers without knowledge of this limitation and will not likely become aware of it until maybe a year or two down the road when their computers may require more RAM. At that point, the memory limitations of 32-bit Vista may become a problem.

Additionally, a similar problem looms over purchasers of many Vista laptops and some desktops. Many recent models and some models being sold today can only physically support 2 GB of RAM. I foresee that many Vista users will need new laptops after only a couple years of use as they begin to require more RAM than their computers will support.

Finally, even if a user can make the decision to purchase a 64-bit version of Vista, they must be careful to ensure that their existing software and peripherals will run under 64-bit Vista. Even if they are planning on purchasing all new software and peripherals, they will still need to ensure compatibility as not everything is 64-bit compatible yet. And going forward, they will need to be diligent that they are purchasing and installing 64-bit versions of new software to get the most out of their 64-bit computer. Again, many people have no idea what the difference between 32 and 64-bit software is, so we may begin to see performance problems with 64-bit computers running mostly 32-bit software in the not-too-distant future.

Already, Vista has 6 different versions (Starter, Home Basic, Home Premium, Business, Enterprise, Ultimate). Add to that the 64-bit versions of each – except Starter which only comes in 32-bit – and you have 11 different Vista versions to choose from! Confused yet? I know I may sound like I repeat myself sometimes in my articles, but perhaps the answer is to simply buy a Mac. Technology should make your life easier, not harder. When you purchase a Mac, you get one operating system that is fully 64-bit, does not suffer from memory limitations, or makes you deal with confusing 32/64-bit compatibility issues.

As usual, please submit any technology questions you may have and your question may be featured in this newsletter!