I found this article over at Tomshardware quite interesting. They have tested a lot of different games, video rendering, mp3 encoding and other benchmarkt tests to see how much difference there is in performance between a 512 MB, a 1GB and a 2GB machine.
How much RAM does your PC have? If you run Windows XP, it is probably in the range of 512 MB to 1 GB. Older Windows versions will do the job with less than that, but as soon as you execute demanding applications or more than one application at a time, anything below 512 MB will likely translate into performance bottlenecks.
Of course, the more RAM you have, the better off you are - but how much memory do you really need?
Multiple software threads that run all at once every time you boot up your PC continue to proliferate. Multitasking software includes what we really need, such as anti-virus tools or firewall software, or useful programs to which we have all grown accustomed that permanently run in the background until they need our direct attention. Most users, for example, have their email client and browser permanently available. Instant messengers such as AIM, ICQ MSN or YIM increasingly pop up on a growing number of desktops, while a media player plays music while you work. And all of these consume some memory, leaving fewer resources available for applications that you want to launch. read more
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