excel out of memory

hi,
we have a win2k Sp4 tserver with office 2000 (excel 9.0.3821Sr-1) on a
dual xeon with 4 Gb ram.

When i open 2 big excel files i get an "out of memory" error in a
little msgbox.

The first file is opened well, but when i try to load the second it
start to open (progress bar is active) but after a while a get the
message.

Is there any workaround (without upgrading ) ?

thanks