Hello There
the Scenario shown seems to indicates several problems :
at first i suggest you to recap completely logic board , even if the capacitors ( 47uF16 v) apparently look good i'm pretty sure they are gone ( if you are good with soldering is not so difficult )
Logic board must be washed very good ( with isopropyl alcool )after having take off old capacitors , then take a look to traces if you see broken and check continuity with multimeter
Replace with new capacitors and good luck.
But if i understand it seems that you have also a problem with analogic board ( no fan , no video)
it should be important to check voltage ( maybe flyback transformer fail) or capacitors inside power supply are gone.
If you are resident in USA the best way is get in touch with Charles Phillips ( www.maccaps.com)
you can find capacitors references and also ask for a complete recap service ( is one of the Best in the World)
Good luck!!