LED on CPU debug, no output
LED on CPU debug, no output
Consider changing the CPU. If the issue remains, the motherboard might be the problem.
If it boots with RAM, it won’t boot without it. Unless there was an issue during installation, then it should function after a proper reinstall and you can update the BIOS normally. The default BIOS setting is 2133 MHz for all new RAM modules, which works with any RAM that supports faster speeds (it will maintain 2133 if it supports 3200).