There is another set of overload fuses (4 to be exact) and a few relays. When I say "under" what I mean is...

in the engine compartment of a 98 V70 (and others) there is a plastic flap latched over the main 30+ fuses. this flap latches to a larger plastic piece that is bolted down with (4) T25 (not T20) Torx screws. Remove these screws and you'll see (4) 20amp 12V overload fuses to the right of the main fuses. Two terminals are wired to the driver/passenger power seat motors. Another goes to power windows, sunroof, etc. You should have at least Two fuses (one for power windows & sunroof and another for drivers power seat). If your power windows work, then take the fuse out of that terminal and try it in the power seat terminal. A quick swap should tell you if your overload fuse is blown. Unlike the main fuses, you can't see the conductor that "melts" if overloaded, so its best to swap out one that you know is working (ie power windows) to check if you blew the fuse.

good luck