New idea! Threads that tickle your senses, run shivers up and down your spine, you want to hug the provider of the solution, or congratulate the OP on the insight.

First point in case: With some hints and advice from well-versed gurus in this forum, the OP managed to reduce the recalculation time of a workbook from 165 minutes to 28 seconds. Not a single line of code or formula was discussed in detail. Great effort from the OP, fantastic mentoring from our gurus!

http://www.excelforum.com/excel-2007...cpu-usage.html