When the iBook flashes the ? on the screen then it means that it can't find an operating system or in your case a hard drive. What you need is a new hard drive because the one that you currently have might have an old spinner inside and because of its age it can only turn under certain circumstances(I think you are mistaking the hard drive noise with the fan noise as these models have fans that only come on at a certain point). If you find an external hard drive you can try and boot from that or you can install an new hard drive inside(ifixit has several great manuals).
Hope this helps.