I changed all peripherals except the board and CPU. Changed 3 PSUs. 5 video cards. 2 SSD. 4 RAM sticks. 3 network cards. Disconnected all fans. Changed cpu fan. So I know this rattle like snake is coming from board. Stethoscope localises it to near CPU, variable voltage modules and RAM. When it happens OS fails to boot. If I unplug and wait 20 minutes then power on it boots OS no problem. But when the rattler sound starts : no boot. Black screen with flashing hyphen. Please, tell me what can possibly make that sound on the board itself (no, not speaker either). Is the board dying? Grateful for advice.