2GB to 4GB?

When I start a run for FEA I can allocate up to ~1.3GB to memory allocation, and the analysis takes 'X' amount of time. Im using 32bit Windows with the 3GB switch enabled.

My question is whether it is worth upgrading from 2GB to 4GB of ram and running Windows x64?

How much ram would I then be able to allocate for the analysis's?

Does it cut down analysis time significantly by allocating more ram?

Thanks...

@1st: Memory allocation is not the amount of memory you can use. You don't need to modify this value, 128 MB is allmost a good value.

@2nd: XP64 with 4GB has not the limit of about 2.9GB usable Memory for pogramms with the 3GB-switch. All available RAM is used by Mechanica. 2 reasons to go with XP64/4GB: the difference between CPU-time and total time is too large (caused from I/O to harddisk) or the analysis stops with fatal error caused from "Memory allocation". In this case I mean, that loop by loop the memory usage is increasing (by the value of memory allocation) and for the next loop the limit of 2,9GB is passed.
HIH Uwe