firstly my indepth knowledge in this area is not good - but in my defence the user didn't specify what operating system he was using so i was trying to cover all bases - with 95, 98 and ME i found 200Mb to be more than adequate with a ram of 520Mb. In fact with using the "conservativeSwopFile" option in config.sys the swop file never got used - i gathered that all shadowing and "paging out" was given to available ram as a priority, and that only in the even that ram became low would the swop file be used. I really gave my system a thrashing and the only time my swop file was used was with one of those large kids games.
However, when it comes to windows XP (which I have only had for 6months) I am a bit lost, as this option of swopping to ram is somewhat limited (as is my knowledge of XP) - but even so, I currently have a 200Mb swop file and have tweaked things as far as XP will allow me and i still haven't gone over a 100Mb on HEAVY load.
What first prompted me to do a lot of trial and error work in this area was it just seemed strange to me that my hard disk was being used all the time (and I had a noisy hard disk at that time) when I had ample free ram which never seemed to be used.
So I think maybe windows XP's recommendation of 150% maybe trying to cover all bases as well - as i think if you have 520Mb ram this does not hold. After all we are talking about "minimum swop file size"!!!!
Would love to hear your thoughts on the matter because i am only just starting to come to grips with XP.
Peter