If you can't even go into the BIOS setup (I assume that's the purpose of F2), it doesn't boot without hard drive and the generic reset (disconnect power, remove battery, hold down power button for 1 minute) doesn't fix that, it's time to ask an estimate for repair. A new motherboard for a laptop is about as expensive as a new laptop, so most of the time a bad idea.
Hi, i was transferring some documents from my laptop to my external hard drive and the laptop just shut down. Since then, it is continually restarting. It boots up, Packard bell screen runs for about 3 seconds then shuts down and repeats. I have disconnected the external hard drive, held down the power button, tried pressing f2, tried entering control panel... Nothing is helping. Does anyone have any advice please?

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