Well, a multimeter to work out which pins short to (ie, are) ground is probably a good start. That both reduces the number of pins to buzz, and might help prevent future experimental damage through short circuits.
Scoping the other pins for signals would depend on convincing the card to output an image though, I guess. If that can be done, your scope should help you detect which pins are carrying signals - even overlaid signals - and deduce the timings. From timing, you (we?) can probably have a stab at which signal is which.
Do integer divisions of any of those frequencies produce any familiar numbers?