I'm sort of late getting into this discussion, but here's how I have linked Excel charts in Powerpoint:
- In a Powerpoint page, Insert/Object/Microsoft Excel Chart
- Hit Delete once to get rid of the preformatted chart there
- Switch to Excel, Copy your chart
- Back to Powerpoint and Paste into the Powerpoint chart window
You have all the charting functions of Excel in the Powerpoint file. When the Excel data is updated, have the file open along with the Powerpoint file. Just double click on the Powerpoint chart and it will refresh with the new data.
Hope this helps!