Apple Power Mac G5 Desktop "repair firewire ports" Questions

firewire ports are suddenlt not working. i think a firewire device might have overloaded them There is a place under your apple that says about this mac. Click there. THen on the bottom of that window

FireWire Port and reboot with option key held down. If you can get your Mac to boot.... Install a clean OS X onto a USB memory Stick (16 or 32gb) Keep this for Booting Problems & Emergency Booting