Keeps rebooting during cold start
Whenever I start the iMac in the morning, I hear the startup sound, but then, at different stages of the boot process, the screen goes black, there is a startup sound again and the process starts from the beginning.
It only happens when the iMac was off for a while. I get around by pressing the Option key during boot and letting is sit for a few minutes at the boot disk choose screen. Then it boots ok.
I have read somewhere that it might be a power supply problem. I have been thinking about replacing the power supply if it gets worse. Did anyone had a similar issue and successfully fixed it?