I imagine that there is some application which nearly runs perfect but not quite smoothly that a little extra boost would run well. Quake 2 for instance doesn't benefit enough to say X is playable but Y is not (all supported resolutions run "well.")
For me it is Amigenerator, the "T" version runs perfect but I prefer the scanlines in the full version at 640x480 and there are little hiccups in the sound, though 33MHz more isn't enough.
I wonder how well the thermal pads are doing their job after 16 years I might try to replace them or just use fresh thermal paste, at least it may just extend the longevity of the cards till Strim makes a new 750FX board at 1GHz.