The AVID Cinema card (video capture) used the DAV slot. That slot is connected to the AV ports on the 8600 so an add on card can bypass the built in AV chips (there is a fat cable connecting the slot to the card). Most people just purchased a decent 3rd party PCI card for video capture and didn't use the DAV slot at all.
Some of the 8600's (604EV processor 300Mhz+) had cache on board so the cache slot on the motherboard was not used. Anybody adding a G3 or G4 upgrade CPU didn't use the cache slot on the motherboard at all (caused stability problems).
Some of the 8600's (604EV processor 300Mhz+) had cache on board so the cache slot on the motherboard was not used. Anybody adding a G3 or G4 upgrade CPU didn't use the cache slot on the motherboard at all (caused stability problems).