A few things to try. First off - you might try version 10.5 if the Beta is still open. I know the launch is not far away and this version has a new data engine included.
Next up, check out Nicholas Hara's post - 6 Tips to Increase Dashboard Performance and several of the other posts that can be located via google search. Reducing the number of marks in the view (#2 on Nick's list) is the item to be most helpful to improve performance.
I hope this helps.
Hi Patrick ,
I reduced marks on the worksheet (which was taking a longer time according to the performance recording ) , and it reduced the time taken to load to 19sec .
Thanks a lot for the link you posted .