I have a desktop with AMD triple core CPU. At start-up, it hangs at BIOS logo, and sometimes the screen goes black.
I can't enter the BIOS settings, because the keyboard doesn't response more than one time (e.g F2 or Tab).
I disconnected all parts (RAM, HDD, Graphics Card), replaced the PSU and Graphics Card, applied new thermal paste to the CPU cooling. I'm not getting any sound alarms.