memory issues with large data set

Hi,
 
I am running R 2.0.1.1. on Windows.  It is a Dell Dimension with a 3.2 Ghz Processor and 4Gb RAM. 
 
When using the ReadAffy() function to read in 97 arrays, I get the below error messages:
Error: cannot allocate vector of size 393529
Reached total allocation of 1024Mb: see help(memory.size)
 
When I use the comman "memory.limit(size=4000)" to increase the memory size to the maximum available, I got a "NULL" as a response.
 
I proceeded to re-run ReadAffy().  This time, I only get the first error message.
Error: cannot allocate vector of size 393529

From what I've read, this is more of a problem with Windows than with R.  But I am wondering if there is anything I can do, either with the set up of R or Windows, to solve this problem and read the data set into R using this machine.

Thank you for your attention,
Christina