A table of memory limits is available on this MSDN article.
A 32-bit process can have a memory address of 2GB in both 32-bit and 64-bit windows.
A 64-bit process can have 2 GB in 64 bit windows and
x64: 8 TB with IMAGE_FILE_LARGE_ADDRESS_AWARE
Intel IPF: 7 TB with IMAGE_FILE_LARGE_ADDRESS_AWARE