There's no answer to that question that's right for everyone. It
depends on what apps you run.
Most people running a common range of business apps should have
a low minimum (say, 200MB) and a very high maximum, to let it
expand as need be.
Disregard Windows poor recommendation based on a multiple of how
much RAM you have, and disregard the advice of those who tell you
to keep the minimum and maximum the same.
If your use of the computer is anything approaching that of mine, which, I
have to admit, is rather pedestrian, then start from 50MB. Using the Page
File Monitor tool ( in the Alex Nichol's article, Rick referred to), my
reading ranged from 12 to 26!! And, I have only 256MB RAM. Maybe, I have
not run this long enough..... I'll wait and see.