Mac Mini stuck on booting
Hi,
My Mac mini is stuck on booting. I see the apple logo and the progress bar reaches halfway and then it restarts again and it repeats. To fix this I tried online suggestions
I removed all the connections except mouse and keyboard and then,
I tried to start in safe mode by pressing 'shift' key while restarting and it ended up with a grey screen with out the apple logo and progress bar.
I tried to start in disk utility mode by pressing cmd + R, no use ended up with the same blank screen.
I also tried cmd+alt+P+R to reset NVRAM and again the same grey screen.
I had a recent backup so I'm not worried about the data and so wanted to reinstall OS but even then cmd + R is also not working.
Is there any other way I can try before taking it to the service centre? Can I reinstall OS through any other option?
Thanks
PV
Mac mini, macOS 10.12