I use Excel a lot to access in Informix database through ODBC. I currently
have a file this is causing problems.

The file is 179Mb in size and has one sheet containing the data from
Informix which has about 14500 rows. On top of that there are 9 - 10 pivot
tables all relating to this data.

Once a month I refresh the data then go through each pivot table and update
it. My problem is that after updating the data and 3 or 4 tables the system
hangs. The CPU has 51% usage by Excel and 49% free.

If on the other hand I do 2 or 3 tables then save the spreadsheet and close
Excel then re-open the file it carries on fine.

Why is this happening? I thought that it was due to lack of RAM but I have
1GB. Is there a setting I need to change or something?