If you need to find out which version of the SAP Gui or SAP BEx analyzer is being used (so you get an idea of how many PC’s needed to be upgraded/patched),
the content of table RSFEC (BW frontend check) can be very helpfull.

In the example above you can see that SAP Gui version 3.0(20), version 3.5(00) and version 3.5(71) are being used.