iMac doesn't boot past white screen with folder and question mark
I have an older iMac that I am trying to revive. When I attempt to turn it on, it boots to a white screen that flashes a folder with a question mark in the middle of it.
I have attempted to use multiple different key combinations to try and boot into safe mode, or disk selection, and none will work. Some key combinations will instead boot to a white screen with the cursor and no folder, but that is at.
I am replacing the hard drive and trying to boot onto a bootable USB, but since they key combination will not boot to the screen I need, I cannot get a new macOS installed.
Is it possible that there is something else going on, or is this iMac just toast?
iMac, Mac OS X (10.7.2)