iMac G5 stuck on a reboot loop

Hello!

I have researched all Communities and googled, however i have not found any solution.

I received an iMac G5 from this old couple, they were going to throw it out, but all it needed was a power supply which I bought and replaced.

It's been about 9 months and everything worked great, no problems whatsoever.

Three days ago, I shutdown the computer and when I booted the next day, it would only reach the Apple logo and the spining wheel, the fans would blast loud and then it would shut down and restart again, repeating the same thing over and over.

I cannot start it under Safe Mode nor it recognizes the CD when booting.

Any help would be appreciated.

Thank you.

iMac G5

1GB Ram

no Isight