Where is the problem?

I’ve just recieved a unit(given)from a friend. When I start it up it starts to register,then it gives me this message: Conflict I/O ports:3F8. It then tels me to run scan disk. After about 2 hours it found and tried to repair 123 sectors. It then says to run scan disk daily for a while. Each time I have done this(2)it finds fewer bad areas, will run in safe mode only. how do I get win 98 to run normal, and or how do I get this system back on line?