I own a G4 power mac and when I start my computer, a gray screen comes on with 2 small images in the middle of the screen switching back and forth. One image is a folder with a question mark on it and the other image is the icon for the finder/hard drive?
It seems as though you don't have an operating system installed on it. You're going to need the operating system discs that came with that Mac.
If by chance you don't have it, you might need to purchase a copy of OS 9 and OS X. The reason I say both is that it is possible that your G4 Mac might need a firmware upgrade that only runs in Mac OS 9. It will NOT run in Classic mode under OS X, since you need to install the firmware upgrade in order to run OS X properly (this firmware upgrade added proper support for OS X on older Macs that didn't ship with it by default).
See here for purchasing Mac OS 9 and Mac OS X (I recommend 10.3 unless you really need the Dashboard and Spotlight in 10.4): http://www.applerescue.com
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