There is one thing that is kinda scary about Vista... In the Task Manager there is a Commit Charge which, correct me if I am wrong, states how much memory is being used by Windows and how much is available to use (Memory + Page File). To tell if you need more memory it is vital to look at this area. Certainly, if your memory in use is above your phyiscal memory then you are using the page file and thus might want more physical memory.
My XP right now at work shows a Commit Charge of 394 M/2443 M. Performance tab (which may matter more) shows a Commit Charge Total of 404 M with a peek of 429 M, Physical Memory has 1039 M total, 528 M Available. So, a Gig of Ram onboard is fine for me speed wise.
I want more pictures of Vista's Task Manger, specifically the performance tab (and a shot of the tasks list at the same period of time. Running with nothing Vista (his copy) has a commit charge of 1169 M, as in Windows has gobbled 1169 M of memory (M being Megabytes), meaning that my system here (and my home system) would be suffering a performance hit becuase there would be paging to the hard drive!! That is only running general Windows stuff too!
Thank goodness memory is cheap. Still, the amount of memory used is insane and certainly any Joe Sixpack with 256 Mb of memory is eliminated from upgrading and the ones who sprung for 512 Mb of memory for speed would barely be able to function. Wow...
<edit> Current tasks on my computer that might be eating memory is AIM Triton, Firefox with 5 tabs, another Firefox window with 1 tab, another Firefox window with 1 tab (Firefox is up to 90 M usage, AIM Triton is at 60 M), and notepad...
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