Data feeding a pivot table approaching 50,000 rows

[MARKSTRO]

What limitations can I expect when I sort multiple columns in the data, currently @ 47,000 rows and columns thru AA.
Occasionally I get a "not responding" error when I try to clear multiple sorts vs. clearing them individually.
My IT Dept tells me I am performing too many calculations when I do this and is causing Excel to go into "not responding" mode and sometimes crashes and needs to restart.
This Data also feeds a pivot table that will not display slicer buttons for data that should be displayed.
There are no calculations being performed in the data set, I add to the data weekly as I receive invoice data from a vendor and then use the pivot table to print out invoices.
Hope I gave enough info to elicit some answers or generate some questions to clarify what I'm asking.
Thanks much, Mark

[Pepe Le Mokko]

Perhaps install the free PowerPivot add-on supplied by MS ( yes, it's free !) and start from there. It will accommodate millions of rows without problems

[MARKSTRO]

Is that my problem, I would think Excel would / should be able to handle that kind of sorting with glitching up like that.
I also cannot solve how a slicer will not show a data field that should be there, what is the significance of the bold text slicer buttons vs. the standard text?