Naturally, a system with low memory runs very slow or even hangs up from time to time. Running multiple programs simultaneously can lead to sluggish systems as the memory resources are used up to run the programs which leaves little for reserve. This might even affect other hardware inside your CPU and could even lead to your computer's total failure. So it is best that you have too much memory than having just enough on your computer system.

Requirements for memory are quite different depending on the operating system you are running. For your operating system to run smoothly and work harmoniously along with the other hardware inside the CPU, you must make sure its compatibility. Windows 98 only required 64k to 128k memory for the system to run at its peak efficiency. But that was a long time ago.

Trends in computer technology never stop and keep on evolving. Therefore, upgrading your computer system is necessary now and then. When windows XP came out to world market, the recommended amount of memory is 256k to 512k with 1GB RAM being the most recommended.

Then new windows Vista operating system has memory requirements that are considerably higher than XP's simply because there is so much more to Vista than XP. Compared to windows XP, many features of windows Vista had been enhanced for faster and better functionality. There are far many more background tasks to take care of, a more complex UI, and a code base that's considerably larger than that of Windows XP, all of which need memory. Almost all of it is already being used whenever you boot up a Vista machine with 512MB of memory.

Microsoft and software makers in general notoriously understate the minimum system memory requirements. Try running windows vista with 512MB of memory. Even if vista disables background tasks and neat effects, your system will certainly slow down still. This is for a fact that 512MB memory doesn't run smoothly in windows vista because their compatibleness is poor. You can get by running a single application, such as IE7 or Outlook, but multitasking is out of the question.

While Windows XP is more tolerable with 512MB, the minimum memory for Vista should really be 1-2 GB. Vista uses a lot more memory and in turn, you'll need quite a bit more memory to get a similar experience to what you had under XP. If you've been tired and annoyed by your computer's speed performance, why not upgrade? As applications and usage models get more demanding, and as memory prices drop, the move to 2GB or even 3GB of memory makes more sense for windows vista systems.