u/Either-Buy-6127

I replaced my old 650W PSU with a new Phanteks AMP GH 750W PSU. After I replaced it the machine won't boot. Two times after unplugging all power etc. it booted, but then the pc went into hibernate after 15 minutes when i came back it wouldnt come back on only showing nothing on the monitors while all the fans and lights are on.
So now it powers on, it sounds like its about to boot up but nothing happens, POST lights goes from CPU and DRAM, then to BOOT and it just stays there. The components inside the pc light up but mouse and keyboard does not.
I have tried resetting CMOS battery, unplugged everything, not sure what else to do other than replacing the PSU?

My motherboard is ASRock b650 pg lightning

After new PSU my PC is not booting