Dumb Question:What does the 4 gig patch do?

[irish1958]

Originally Posted by Kpt. Hess

From the author's commentary on the program:



This flag defines whether the file is allowed to access more than 2 GB or not, so it just comes down to a very small simple change - but one with great effect.

To clarify, is that for XP, 32 or 64 bit only or does it pertain to Vista/Windows7, 32 or64 bit also?
Or to state the question another was, what operating systems should use the 4Gb patch, and which do not need it (for SHIII, IV, V)?