How can I reduce memory and CPU% used in Excel 2007?

I have tried the SaveAs method in VB between Excel function calls, where I save the Excel file under another name, then kill the Excel process, and then re-instantiate another Excel process for the next function.  I don't just use a Workbook.Quit command, I actually terminate the Excel application in the Task Manager so that the memory is freed up (I think).

However, when I re-instantiate Excel app based on the previously saved file, it starts up around 52,000K, then when I start the workbook, it jumps up another 79,000K.  Is there anything I can do to bring down both the memory used and the CPU % used?

Also, some of the Excel functions are extremely long, and there is no way I can break them up.  By the time the function is finished, the memory and CPU % used almost crash the pc.  I can only use the SaveAs method in VB outside the Excel function.  Within the Excel function I can't do anything to kill Excel and re-instantiate, so the memory used just keeps growing until the long loop is finished.

Any suggestions would be appreciated.
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Ingeborg Hawighorst (Microsoft MVP / EE MVE)Microsoft MVP ExcelCommented:
Hello IndyJoe,

there's probably no easy and simple answer to your question. It may actually take a lot of work to fix it.

Here is an excellent article by Charles Williams about Improving Performance in Excel 2007.

It touches on many aspects of Excel, from formulas to used ranges to VBA.

I'm sure you'll find something worth considering in there.

cheers, teylyn

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