I changed PSU on my PC today while I was cleaning my pc from dust and now when I turn it on the monitor goes into sleep mode and nothing happens, no beeps, no image. All of the vents are working the new PSU is working. I tried to put the old PSU and it doesn't work with it either, tried cleaning the ram slots and nothing happened, tried to restart bios and nothing happened.
More aboutblack screen startup beeps
I suggest removing all components/cables but CPU and CPU fan, reinstall them and test.
I solved the problem, took out ram and then put it back it and now it works fine, thx anyways